quantum physics in one dimension - unige · plan of the lectures lecture 1: basic concepts for...
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Quantum physics
in one dimension
T. Giamarchi
http://dqmp.unige.ch/giamarchi/
N. Kestin A. Kantian
S. Furuya
E. CoiraL. Foini
C. Berthod
N. Kamar
A. Tokuno
S. Tapias
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
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
Effect of interactions
Landau Fermi liquid
Individual fermionic excitations
exist (quasiparticles)
*m m
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
Photoemission
Measures Spectral function A(k,)
4 3 2 1 0
binding energy
0°
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)
(M. Grioni)
T. Valla et al. PRL 83 2085 (1999)
Mo(110) surface
• Transistor 1956
• Supraconductivité
• Magnétorésistance
géante
(1913),1972,
1973,1987,2003
2007
Need to undestand the effects
of interactions ?
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
Finding new functionalities
/physics
(Y. Tokura, Japan)
Ferroelectrics, High Tc, Manganites,
Oxydes, Organics,, nanomaterials....
10 23 particules + Interactions:
Crucial fundamental problem
``non Fermi liquids’’
tomorrow’s materials
1 μm
Reduced dimensionality
Future electronic
Need to worry about reduced dimensionality
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…
One dimension is specially
interesting
• No individual excitation can exist (only
collective ones)
• Strong quantum fluctuations
Difficult to order| | ie
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 !
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)
What does “1D” means in the real
(3D ?) world
22
2 2
2
yx
y
y
kkE
m m
nk
L
Fine …..
But does it exist ?
TG, Int J. Mod. Phys. B 26 1244004 (2012)
Organic conductors
c
b
D. Jaccard et al., J. Phys. C, 13 L89 (2001)
Cees Dekker
CARBON NANOTUBES
Quantum Wires
O.M Ausslander et al., Science 298 1354 (2001)
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
Cold atoms
Control on the dimension
I. Bloch, Nat. Phys 1, 23 (2005)
Typical problem (e.g. Bosons)
• Continuum:
• Lattice:
How to treat ?
``Standard’’ many body theory
Exact Solutions (Bethe ansatz)
Field theories
(bosonization, CFT)
Numerics
(DMRG, MC, etc.)
Luttinger liquid physics
Labelling the particles
1D: unique way
of labelling
(x) varies slowly
CDW
~ 0q 0~ 2q
: superfluid phase
Quantum
fluctuations
U0 1
K1 1
Luttinger liquid concept
• How much is perturbative ?
• Nothing (Haldane):
provided the correct u,K are used
• Low energy properties: Luttinger liquid
(fermions, bosons, spins…)
Correlations
1/2
S(q,!) J.S. Caux et al PRA 74 031605 (2006)
Finite temperature
Conformal theory
b
c
K
r
21
bb
/)2(
x
xK
ee
Fermions
Right (+kF) and left (-kF) particles
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
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.
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
Luttinger parameters
M. Klanjsek et al., PRL 101 137207 (2008)
NMR relaxation rate:
Tests of Luttinger liquids
Organic conductors
c
b
A. Schwartz et al. PRB 58 1261 (1998)
First observation of LL/powerlaw !!
TG PRB (91) :
Physica B 230 (1996)
Z. Yao et al. Nature 402
273 (1999)
Cold atoms
Bosons (continuum)
Optical lattices (dilute)
B. Paredes et al., Nature 429 277 (2004)
†( ) ( ) (0)ikxn k dxe x
I am your worst nightmare
Confining potential / Trap
3 2 2
0
1( )
2H d r r r
• No homogeneous phase !
Atom chips
K large (42)
S. Hofferberth et al. Nat. Phys 4
489 (2008)†
0( ) (0)
L
dr r
Magnetic insulators
Bose Einstein Condensation
(TG and A. M. Tsvelik PRB 59 11398 (1999))
triplon = hard core boson
h hc dilute limit: « free » bosons
BEC vs BEC
Cold atoms Dimers/Spins
TG, Ch. Rüegg,
O. Tchernyshyov,
Nat. Phys. 4 198 (08)
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)
Luttinger parameters
M. Klanjsek et al., PRL 101 137207 (2008)
Red : Ladder (DMRG)
Green: Strong coupling (Jr 1 ) (BA)
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)
M. Klanjsek et al.,
PRL 101 137207 (2008)
NMR
D. Schmidiger et al. PRL 108 167201 (12):
K. Yu et al. arxiv/1406.6876 (14)
†
, ,q qS S
Spin ladders
Fractionalization of excitations
1 = ½ + ½
E(k) = cos(k1) + cos(k2)
k = k1 + k2
Neutron scattering
B. Thieleman et al. PRL 102, 107204 (2009)
P. Bouillot et al. PRB 83, 054407 (2011)
Spin
Spin-Charge Separation
Charge
Spinon Holon
Spin
Spin-Charge Separation
higher D ?
Charge
Energy increases with spin-charge separation
Confinement of spin-charge: « quasiparticle »
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)
A. Kleine, C. Kollath et al. PRA 77 013607 (2008); NJP 10 045025 (2008)
Proposal for cold atoms (Rb)
End of the story ...... ??????
Quantitative agreement with the
predictions of the Luttinger liquid
NO! Luttinger liquid plays the
same role than Fermi liquid did
To boldly go where no theorist
has gone before….
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)
• 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).
Mott transition
Lattice: Mott transition
Costs U
Quantum phase transition
SU MI U
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
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)
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
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
E. Haller et al. Nature 466 597 (2010)
Disorder and interaction effects
Dirty bosons
TG + H. J. Schulz EPL 3 1287 (1987); PRB 37 325 (1988)
``Two’’ fourier components of disorder
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)
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)
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),…….
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
Hunt for the Bose glass
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)
…..
Old Experiments
Josephson junction arrays
Disordered superconducting films(D.B. Haviland et al, PRL 62 2180 (89))
Helium in porous media
New remarkable systems
Cold atoms
New superconducting films
Spin dimers
Comptes Rendus AS
Cold atomic gases
Speckle (Palaiseau,
Florence, Urbana)
Biperiodic lattices
(Florence)
Mixtures
(Stony Brook)
Quasi-periodic
Quasiperiodic (1D):
J. E. Lye, et al., PRA 75, 061603R 2007.
L. Fallani, et al. PRL 98, 130404 2007
Speckle
Pasienski et al. Nat. Phys 6 677 (2010)
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)
• Reentrant phase diagram (consistent with theory)
• Disordered insulator (``Bose glass’’)
• But one can improve on : temperature, Mott
insulator, trap
Absence of equilibrium: MBL
Artificial Gauge fields
Meissner effect in bosonic
ladders
E. Orignac, TG, PRB 64 144515 (2001)
A dl
Orbital currents (``Meissner’’ effect)
Field ``Hc1’’: appearance of vortices
Observed in cold atoms (I. Bloch’s group)
Interactions: devil’s staircase
Plateau at ½ should be visible
Fermionic ladders
Many works (Nersesyan, Lehur, Roux, ……)
Experimental realisations ?
Unconventional superfluidity in
fermionic ladders
S. Uchino, A. Tokuno, TG,
PRA 89 023623 (2014)
Zero flux: singlet superconductivity
(d-wave U >0 , s-wave U < 0)
Triplet superconductivity with purely
local interactions !
Other/related route:
State dependent hopping
S. Uchino, TG,
PRA 91 013604 (2015)
Challenge: t_up = - t_down
Shaking or artificial gauge fields
Triplet
superconductivity
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)
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
Trapped/open
regimes
Light cone of
spinless bosons
M. B. Zvonarev, V. V. Cheianov, TG, PRL 99 240404
(2007)
Experiments: Cambridge, Florence,
Innsbruck, Munich, Bonn, …
Theories: Akhanjee, Tserkovnyak, Matveev,
Furusaki, Kamenev, Glazman, Gangardt,
Lamacraft, ……
Driven impurity
Diffusive impurity
J. Catani et al. PRA 85, 023623 (2012)
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
Ferromagnetic Heisenberg
Coherent propagation of a magnon
Heisenberg model : ex 1·i i
i
H J S S 2
ex
4JJ
U
Impurity in a LL (weak lattice)
Polaronic effect
Driven impurity vs diffusion
• Normal transport
• Einstein relation: = D
Coupled 1D chains:
deconfinememt
“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
Higgs “amplitude” mode
AF Ho, M.A. Cazalilla, TG,NJP 8 158 (2006).
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)
Cold atoms
AF Ho, M.A. Cazalilla, TG, PRL 95, 226402 (2005);
Arxiv/0604525
Triplet
superconductor
(repulsive
interactions)
Out of equilibrium Luttinger
liquids
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
E. Dalla Torre, E. Demler,TG, E. Altman, Nat. Phys. 6 806
(2010); PRB 85 184302 (2012)
LL + external noise
And many other problems
and works……
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