quantum semiconductor electronics department of electronic

H I RAKAWA GROUP [QuantumNanophysicsanditsDeviceApplica@ons]

NanoscienceCenterforPhotonics,Electronics,andMaterialsEngineering

QuantumSemiconductor E lectronics

Terahertzphotodynamicsanddeviceapplicationsofquantumnanostructures Ee202

Department of E lectronic Engineer ingand Informa@onSystems hLp://thz. i i s .u-tokyo.ac. jp

Quantumnanophysicsanditsdeviceapplica3ons

Variousintriguingphysicsshowsupinquantumnanostructuresowingtosizequan@za@onandelectron-electroninterac@oneffects.Weinves@gatenovelphysicsinsuchquantumnanostructuresandexploretheirdeviceapplica@ons.

■ Carrierdynamicsanddeviceapplica@onsofquantumnanostructuresintheTHzrange ■ Nanoscienceforsinglemoleculartransistors■ Novelhigh-sensi@vity,fastterahertzdetectorsusingMEMSresonators■ Thermioniccoolingeffectinsemiconductorheterostructures

Bloch oscillation in semiconductor superlattices and its application to THz oscillators

Fabrication of atomic-scale nanogap electrodes and single molecular transistors

Thermionic cooling in semiconductor heterostructures

-1 0 1 2 3 4Time (psec)

T = 10K

THz

elec

tric

field

, ETH

z (arb

. uni

ts)

1

11

21

31

Fb = 39 kV/cm

GaAs (6.5 nm)/Al0.3

Ga0.7

As (2.5 nm) SL

femtosecond laser

VG#(V)�

V SD#(m

V)�

C84�DrainSource

Gate

DrainSource

Gate

20

30

40

Time (s)

GJ (2

e2 /h)

0.3

0.4

0.5

0.6

VJ (V

)

VJ#

100#s#

GJ# Au#

VC#

-100�

-50�

0�

50�

100�

-20� -15� -10� -5�

VG (V)�

VS

D (m

V)�

N�N-1�

Sample A �

1#nm�

Development of uncooled, high-sensitivity terahertz detectors using MEMS resonators

NiCr����

120μm�

���� ��� Au�����

AuGeNi�������

PE�

VOx� MEMS�

(pyroelectric)�

NEDT~1 mK/√Hz�

NEDT~1 µK/√Hz�

-35 -30 -25 -20 -15 -10 -5 0

Δf (kHz)

Vo(

x) (m

V)

0 µW 390 µW 800 µW 640 µW 500 µW 200 µW