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Page 1: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Quantum physics

in one dimension

T. Giamarchi

http://dqmp.unige.ch/giamarchi/

Page 2: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

N. Kestin A. Kantian

S. Furuya

E. CoiraL. Foini

C. Berthod

N. Kamar

A. Tokuno

S. Tapias

Page 3: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Plan of the lectures

Lecture 1: basic concepts for interacting

quantum systems

Lecture 2: : basic concepts for interacting

quantum systems

Lecture 3: One dimensional systems; Concept of

Tomonaga-Luttinger liquid.

Lecture 4: Experimental realizations

Lecture 5: Beyond Tomonaga-Luttinger liquids

Page 4: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

References for Lecture 1&2

Lectures Les houches (Singapore) 2009, TG

arXiv:1007.1030

Lectures Les Houches 2010, A. Georges + TG

arXiv:1308.2684

Basic course on many-body physics

http://dqmp.unige.ch/giamarchi/local/people/

thierry.giamarchi/pdf/many-body.pdf

Page 5: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Effect of interactions

Landau Fermi liquid

Individual fermionic excitations

exist (quasiparticles)

*m m

Page 6: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Fermi liquid theory

• Shown perturbatively in U

• Much more general and robust

Element m*/m c/c0

Nb 2 1

3He 6 20

Heavy fermion 100 100

Page 7: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems
Page 8: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Photoemission

Measures Spectral function A(k,)

Page 9: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

4 3 2 1 0

binding energy

60°

em

issio

n a

ng

le

E(k)

wave vector [Å-1]

bin

din

g e

nerg

y [eV

]

EF

-4

-3

-2

-1

0

1.51.00.50.0

zoomed

Bandmapping

[001]

[111]

[110]

X

L

W

.

..

Cu Fermi surface (Ashcroft/Mermin)

Fermi surface mapping

k(EF)

Page 10: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

(M. Grioni)

Page 11: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

T. Valla et al. PRL 83 2085 (1999)

Mo(110) surface

Page 12: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

• Transistor 1956

• Supraconductivité

• Magnétorésistance

géante

(1913),1972,

1973,1987,2003

2007

Page 13: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Need to undestand the effects

of interactions ?

Page 14: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Doped SrTiO3

CMR-manganites

Organics, fullerenes,

novel compounds

largest polarization

reached by the

field effect in oxides

FM-insulator

FM-M

High-Tc cupratesSC metalAF-insulator

SC

AF-M

Silicon, GaAssemiconductor (Wigner, FQHE)

n 2D ( e / cm2 )10 1510 7 10 9 10 1310 1110 5

AF-insulator

FM-I

insulator / semiconductor / metal metal

Densities

Page 15: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Finding new functionalities

/physics

(Y. Tokura, Japan)

Page 16: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Ferroelectrics, High Tc, Manganites,

Oxydes, Organics,, nanomaterials....

10 23 particules + Interactions:

Crucial fundamental problem

``non Fermi liquids’’

tomorrow’s materials

1 μm

Page 17: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Reduced dimensionality

Page 18: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Future electronic

Need to worry about reduced dimensionality

Page 19: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Physics at the edge

LaO/StO interface

(JM Triscone et al.)

Presence of edge

(B. I. Halperin)

Quantum hall effect

Topological insulators….

Superconductivity

between insulators…

Page 20: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

One dimension is specially

interesting

• No individual excitation can exist (only

collective ones)

• Strong quantum fluctuations

Difficult to order| | ie

Page 21: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Three urban legends about 1D

It is a toy model to understand higher

dimensional systems.

It does not exist in nature ! This is only for

theorists !

Everything is understood there anyway !

Page 22: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

References

TG, arXiv/0605472 (Salerno lectures)

TG, Quantum physics in one

dimension, Oxford (2004)

M. Cazalilla et al.,

Rev. Mod. Phys.83 1405 (2011)

TG, Int J. Mod. Phys. B 26 1244004 (2012)

Page 23: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

What does “1D” means in the real

(3D ?) world

Page 24: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

22

2 2

2

yx

y

y

kkE

m m

nk

L

Page 25: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Fine …..

But does it exist ?

TG, Int J. Mod. Phys. B 26 1244004 (2012)

Page 26: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Organic conductors

c

b

D. Jaccard et al., J. Phys. C, 13 L89 (2001)

Page 27: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Cees Dekker

CARBON NANOTUBES

Page 28: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Quantum Wires

O.M Ausslander et al., Science 298 1354 (2001)

Page 29: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Spin chains and laddersB. C. Watson et al., PRL 86 5168 (2001)

M. Klanjsek et al.,

PRL 101 137207 (2008)

B. Thielemann et al.,

PRB 79, 020408® 2009

Page 30: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Cold atoms

Page 31: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Control on the dimension

I. Bloch, Nat. Phys 1, 23 (2005)

Page 32: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Typical problem (e.g. Bosons)

• Continuum:

• Lattice:

Page 33: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

How to treat ?

Page 34: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

``Standard’’ many body theory

Exact Solutions (Bethe ansatz)

Field theories

(bosonization, CFT)

Numerics

(DMRG, MC, etc.)

Page 35: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Luttinger liquid physics

Page 36: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Labelling the particles

1D: unique way

of labelling

Page 37: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

(x) varies slowly

CDW

~ 0q 0~ 2q

Page 38: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

: superfluid phase

Quantum

fluctuations

U0 1

K1 1

Page 39: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Luttinger liquid concept

• How much is perturbative ?

• Nothing (Haldane):

provided the correct u,K are used

• Low energy properties: Luttinger liquid

(fermions, bosons, spins…)

Page 40: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Correlations

1/2

Page 41: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

S(q,!) J.S. Caux et al PRA 74 031605 (2006)

Page 42: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Finite temperature

Conformal theory

b

c

K

r

21

bb

/)2(

x

xK

ee

Page 43: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Fermions

Right (+kF) and left (-kF) particles

Page 44: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Spins

Powerlaw correlation functions

Non universal exponents K(h,J)

Use boson or fermions mapping

( 1) cos(2 )i i iS e e

1(-1) cos(2 )z iS

Page 45: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Calculation of Luttinger

parameters

• Trick: use thermodynamics and BA or numerics

• Compressibility: u/K

• Response to a twist in boundary: u K

• Specific heat : T/u

• Etc.

Page 46: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Tonks limit

U = 1 : spinless fermions

Not for n(k) : F B

Free fermions: 2

1( ) (0) cos(2 )Fx k x

x

K=1

Note: 1/2

† 1( ) (0)B Bx

x

Page 47: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Luttinger parameters

M. Klanjsek et al., PRL 101 137207 (2008)

NMR relaxation rate:

Page 48: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Tests of Luttinger liquids

Page 49: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Organic conductors

c

b

A. Schwartz et al. PRB 58 1261 (1998)

First observation of LL/powerlaw !!

TG PRB (91) :

Physica B 230 (1996)

Page 50: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Z. Yao et al. Nature 402

273 (1999)

Page 51: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Cold atoms

Page 52: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Bosons (continuum)

Page 53: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Optical lattices (dilute)

B. Paredes et al., Nature 429 277 (2004)

†( ) ( ) (0)ikxn k dxe x

Page 54: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

I am your worst nightmare

Confining potential / Trap

3 2 2

0

1( )

2H d r r r

• No homogeneous phase !

Page 55: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Atom chips

K large (42)

S. Hofferberth et al. Nat. Phys 4

489 (2008)†

0( ) (0)

L

dr r

Page 56: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Magnetic insulators

Page 57: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Bose Einstein Condensation

(TG and A. M. Tsvelik PRB 59 11398 (1999))

triplon = hard core boson

h hc dilute limit: « free » bosons

Page 58: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

BEC vs BEC

Cold atoms Dimers/Spins

TG, Ch. Rüegg,

O. Tchernyshyov,

Nat. Phys. 4 198 (08)

Page 59: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Spin dimer systemsB. C. Watson et al., PRL 86 5168 (2001)

M. Klanjsek et al.,

PRL 101 137207 (2008)

B. Thielemann et al.,

arXiv:0809.0440 (2008)

Page 60: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Luttinger parameters

M. Klanjsek et al., PRL 101 137207 (2008)

Red : Ladder (DMRG)

Green: Strong coupling (Jr 1 ) (BA)

Page 61: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Correlation functions

NMR relaxation rate:

Tc to ordered phase: 1/J’ =c 1D(Tc)

M. Klanjsek et al., PRL 101 137207 (2008)

R. Chitra, TG PRB 55 5816 (97); TG, AM Tsvelik PRB 59 11398 (99)

Page 62: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

M. Klanjsek et al.,

PRL 101 137207 (2008)

NMR

Page 63: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

D. Schmidiger et al. PRL 108 167201 (12):

K. Yu et al. arxiv/1406.6876 (14)

, ,q qS S

Spin ladders

Page 64: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Fractionalization of excitations

Page 65: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

1 = ½ + ½

E(k) = cos(k1) + cos(k2)

k = k1 + k2

Page 66: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Neutron scattering

B. Thieleman et al. PRL 102, 107204 (2009)

Page 67: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

P. Bouillot et al. PRB 83, 054407 (2011)

Page 68: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Spin

Spin-Charge Separation

Charge

Spinon Holon

Page 69: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Spin

Spin-Charge Separation

higher D ?

Charge

Energy increases with spin-charge separation

Confinement of spin-charge: « quasiparticle »

Page 70: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

O.M Ausslander et al., Science

298 1354 (2001)

Y. Tserkovnyak et al., PRL 89

136805 (2002)

Y. Tserkovnyak et al., PRB 68

125312 (2003)

Page 71: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

A. Kleine, C. Kollath et al. PRA 77 013607 (2008); NJP 10 045025 (2008)

Proposal for cold atoms (Rb)

Page 72: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

End of the story ...... ??????

Quantitative agreement with the

predictions of the Luttinger liquid

NO! Luttinger liquid plays the

same role than Fermi liquid did

Page 73: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

To boldly go where no theorist

has gone before….

Page 74: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Beyond Luttinger liquids

• 1D additional perturbation:

Lattice (Mott transition), disorder (Bose glass) etc.

Multicomponents, mixtures, …..

• Out of equilibrium situations

A. Mitra, TG, Phys. Rev. Lett. 107, 150602 (2011)

E. Dalla Torre, E. Demler,TG, E. Altman, Nat. Phys. 6

806 (2010); PRB 85 184302 (2012)

Page 75: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

• Impurities, polarons in 1D systems:

• Ladders and magnetic fields:E. Orignac, TG Phys. Rev. B 64, 144515 (2001)

M. Atala et al., arxiv/1402.0819

• Dimensional crossover 1d – 2d/3d:AF Ho, M.A. Cazalilla, TG, PRL 92 130403

(2004);NJP 8 158 (2006).

Page 76: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Mott transition

Page 77: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Lattice: Mott transition

Costs U

Quantum phase transition

SU MI U

Page 78: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Superfluid

Mott

Insulator

Mott transition and cold atoms

Lase

r

Lase

r

[D. Jaksch et al. PRL 81 (1998)]

[M Greiner et al. Nature, 415 (2002)]

Superfluid to Mott insulator

transition in a 3D optical

lattice

Page 79: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

How to treat?

• Incommensurate: Q 2 0

• Commensutate: Q 2 0

cos(2 ( ) )H dx x x

cos(2 ( ))H dx x

0 cos( ) ( )H dxV Qx x

0(2 2 ( ))

0 0cos( )i x x

H dxV Qx e

TG, Physica B

230 975 (97)

Page 80: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Competition

2 210 [ ( ( , )) ( ( , )) ]

2xu

dxdS x u x

K

Beresinskii-

Kosterlitz-Thouless

transition at K=2

String order

parameter

0 0 cos(2 ( ))LS V dxd x

Page 81: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Mott insulator:

is locked

Density is fixed

Gap in the excitation spectrum

n(k)T. Kuhner et al. PRB 61 12474 (2000)

TG, Physica B

230 975 (97)

/( ) rG r e

Page 82: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

E. Haller et al. Nature 466 597 (2010)

Page 83: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems
Page 84: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Disorder and interaction effects

Page 85: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Dirty bosons

TG + H. J. Schulz EPL 3 1287 (1987); PRB 37 325 (1988)

``Two’’ fourier components of disorder

Page 86: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Bose glass phase

U

[interactions]

Db

0

Uc

Bose GlassSuperfluid

TG + H. J. Schulz EPL 3 1287 (87); PRB 37 325 (1988);

M.P.A. Fisher et al. PRB 40 546 (1989)

Page 87: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

SU-BG transition in d=1

Universal exponent at the SU-BG transition !

Db

0 K

Two loop RG:

Z. Ristivojevic, A. Petkovic, P. Le Doussal, TG PRL (2012)

Page 88: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Various phases

• Mott insulator: incompressible; h i = 0

0dN

d

• Superfluid: compressible; h i 0

0dN

d

• Bose Glass : compressible; h i = 0

0dN

d

TG, P. le Doussal PRB 53 15206 (96); T. Nattermann et al. PRL 91

056603 (03); E. Altman et al PRB 81 174528 (10),…….

Page 89: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Other potentials: Biperiodics

G. Roux et al. PRA 78 023628 (2008);

T. Roscilde, Phys. Rev. A 77, 063605 2008;

X. Deng et al PRA 78, 013625 (2008);

Effect of interactions?

Same as ``true’’ disorder ?

J. Vidal, D. Mouhanna, TG PRL 83 3908 (1999);

PRB 65 014201 (2001)

0 0 1 1( ) cos( ) V cos( )V x V Q x Q x

• U= 0

Aubry-André model

• Localization transition

Page 90: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Hunt for the Bose glass

Page 91: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Numerics (disorder)

S. Rapsch, U. Schollwoeck,

W. Zwerger EPL 46 559

(1999);

G. Batrouni et al. PRL 65

1765 (90);

N. V. Prokof'ev and B. V.

Svistunov, PRL 80 4355

(96);

N. Prokofev et al. PRL 92

015703 (04);

O. Nohadani et al. PRL 95,

227201 (05)

K. G. Balabanyan et al. PRL

95, 055701 (05);

L. Pollet et al. PRL 103,

140402 (2009)

…..

Page 92: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Old Experiments

Josephson junction arrays

Disordered superconducting films(D.B. Haviland et al, PRL 62 2180 (89))

Helium in porous media

Page 93: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

New remarkable systems

Cold atoms

New superconducting films

Spin dimers

Page 94: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Comptes Rendus AS

Page 95: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Cold atomic gases

Speckle (Palaiseau,

Florence, Urbana)

Biperiodic lattices

(Florence)

Mixtures

(Stony Brook)

Page 96: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Quasi-periodic

Quasiperiodic (1D):

J. E. Lye, et al., PRA 75, 061603R 2007.

L. Fallani, et al. PRL 98, 130404 2007

Page 97: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Speckle

Pasienski et al. Nat. Phys 6 677 (2010)

Page 98: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Control of Interactions and

Disorder

C. D Errico, E. Lucioni, L. Tanzi, L. Gori, G. Roux,

I. P. McCulloch, TG, M. Inguscio, G. Modugno,

PRL 113, 095301 (2014)

L. Gori, T. Barthel, A. Kumar, E. Lucioni, L. Tanzi,

M. Inguscio, G. Modugno, TG, C. D'Errico, G. Roux

PRA 93, 033650 (2016)

Page 99: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

• Reentrant phase diagram (consistent with theory)

• Disordered insulator (``Bose glass’’)

• But one can improve on : temperature, Mott

insulator, trap

Page 100: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Absence of equilibrium: MBL

Page 101: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Artificial Gauge fields

Page 102: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Meissner effect in bosonic

ladders

E. Orignac, TG, PRB 64 144515 (2001)

Page 103: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

A dl

Page 104: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Orbital currents (``Meissner’’ effect)

Field ``Hc1’’: appearance of vortices

Observed in cold atoms (I. Bloch’s group)

Page 105: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Interactions: devil’s staircase

Plateau at ½ should be visible

Page 106: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Fermionic ladders

Many works (Nersesyan, Lehur, Roux, ……)

Experimental realisations ?

Page 107: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Unconventional superfluidity in

fermionic ladders

S. Uchino, A. Tokuno, TG,

PRA 89 023623 (2014)

Page 108: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Zero flux: singlet superconductivity

(d-wave U >0 , s-wave U < 0)

Page 109: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Triplet superconductivity with purely

local interactions !

Page 110: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Other/related route:

State dependent hopping

S. Uchino, TG,

PRA 91 013604 (2015)

Page 111: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Challenge: t_up = - t_down

Shaking or artificial gauge fields

Triplet

superconductivity

Page 112: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Non-LL and impurity problems

M. B. Zvonarev, V. V. Cheianov, TG,

PRL 99 240404 (2007)

A. Kantian, U. Schollwöck, and T. Giamarchi

PRL 113, 070601 (2014)

Page 113: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Interacting 1D system (Luttinger liquid):

e.g. bosons -- ``spin up’’

Add one particle of ``spin down’’, or flip a spin

Example: two component bose-Hubbard model

( , ) ( , ) (0,0)G x t S x t S

Page 114: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Trapped/open

regimes

Light cone of

spinless bosons

M. B. Zvonarev, V. V. Cheianov, TG, PRL 99 240404

(2007)

Page 115: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Experiments: Cambridge, Florence,

Innsbruck, Munich, Bonn, …

Theories: Akhanjee, Tserkovnyak, Matveev,

Furusaki, Kamenev, Glazman, Gangardt,

Lamacraft, ……

Page 116: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Driven impurity

Page 117: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Diffusive impurity

J. Catani et al. PRA 85, 023623 (2012)

Page 118: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

T. Fukuhara, A. Kantian, M. Endres, M. Cheneau,

P. Schauss, S. Hild, D. Bellem, U. Schollwock, TG,

C. Gross, I. Bloch, S. Kuhr , Nat. Phys. (2013)

Coherent spin excitation

Heisenberg ferromagnet

Page 119: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Ferromagnetic Heisenberg

Page 120: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Coherent propagation of a magnon

Heisenberg model : ex 1·i i

i

H J S S 2

ex

4JJ

U

Page 121: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Impurity in a LL (weak lattice)

Page 122: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Polaronic effect

Page 123: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Driven impurity vs diffusion

• Normal transport

• Einstein relation: = D

Page 124: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Coupled 1D chains:

deconfinememt

Page 125: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

“Mott” potential: localizes atoms

Mott vs. Josephson

AF Ho, M.A. Cazalilla, TG, PRL 92 130403 (2004);

NJP 8 158 (2006).

R’

RJosephson coupling: delocalizes atoms

Page 126: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Higgs “amplitude” mode

AF Ho, M.A. Cazalilla, TG,NJP 8 158 (2006).

Page 127: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

c

b

D. Jaccard et al., J. Phys. C, 13 L89 (2001)

Deconfinement

0 5 10 15 20 25

60

80

100

200

400

600 TMTTF2PF

6

a

T*

IC

SDW

C

SDWSpin-Peierls

c

Act

ivat

ion e

ner

gy,

T* (

K)

Pressure (kbar)

P. Auban-Senzier, D. Jérome, C. Carcel and J.M. Fabre J de Physique IV, (2004)

A. Pashkin, M. Dressel, M. Hanfland, C. A. Kuntscher, PRB 81 125109 (2010)

TG Chemical

Review 104 5037

(2004)

Page 128: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Cold atoms

AF Ho, M.A. Cazalilla, TG, PRL 95, 226402 (2005);

Arxiv/0604525

Triplet

superconductor

(repulsive

interactions)

Page 129: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Out of equilibrium Luttinger

liquids

Page 130: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Quenches and thermalization in LL

A. Mitra, TG,

Phys. Rev. Lett. 107, 150602

(2011)

Phys. Rev. B 85, 075117 (2012)

J. Lancaster, TG, A Mitra,

Phys. Rev. B 84, 075143 (2011)

Thermalization for the low energy part

Out of equilibrium sine-Gordon

Page 131: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

E. Dalla Torre, E. Demler,TG, E. Altman, Nat. Phys. 6 806

(2010); PRB 85 184302 (2012)

LL + external noise

Page 132: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

And many other problems

and works……

Page 133: Quantum physics in one dimension - UNIGE · Plan of the lectures Lecture 1: basic concepts for interacting quantum systems Lecture 2: : basic concepts for interacting quantum systems

Conclusions

Tour of one dimensional physics

Luttinger liquid theory provides a framework to

study this physics, and to go beyond

Many effects: lattice, disorder, long range forces,

competition between orders, out of equilibrium

physics, gauge fields,…..

Many recent excellent realization of 1D/Q-1D

experimental systems