Semiconductor NanostructureAcoustodynamics

Jens Ebbecke

Linz 25/06/09

outline

acoustoelectrics acoustooptics fibres and hybrids

GaAs

kikklikli

kkijklijklij

ESeD

EeScT

one kind of solutions: surface acoustic waves

first investigated in 1885 by Lord Rayleigh for earth quakes

surface acoustic waves

f = cSAW / p

nanostructure

Surface Acoustic Waves and

Semiconductor Nanostructures:

the electronic part

Acoustoelectric Current Device (SET-SAW)

3 m

100 nm

700 nm

700 nm

RF Drive ofFrequency f

Current = e·f

Gate Voltage

Current Plateaus

f = 3.58 GHz

P = 16 dBm

T = 1.7 K

I = e f

-2.2 -2.1 -2.0 -1.9

0

1

2

3

4

5

.

Cur

rent

/ nA

Gate Voltage / V

700 nm

700 nm

Vgate

2D data

Vgate

RF Amplitude

I=2ef

I=ef

I=3ef

RF Amplitude

-1.1

2 V

-1.2

0 V

Interaction of SAW and Impurity dot

Vga

te

RF Amplitude-30 dBm 0 dBm

PRB 68, 245310, (2003)

charging energy of a conductor: EC = e2/C Coulomb blockade

EC = e2/C >> kBT

RT >> h/2e2

zero-dimensional electronic system:

energy quantisation :

total energy:

Δ E = EN+1 - EN = Δ + EC

EF ΔE

Semiconductor quantum dots

quantized current through a static quantum dot

APL 84, 4319 (2004)

RF Amplitude

Gat

e V

olta

ge

I = 1 ef I = 1·e·f

I = 1 e f

I = 2 e f

I = 3 e f.

..

.

..

0

2

Cur

r.

/ n

A

I = e·f

Acoustic turnstile device

-1.1

2 V

-1.2

0 V

V

gate

RF Amplitude-30 dBm 0 dBm

a) b)

a)

Exciting: an Archimedian screw for electrons

PRB 72, 121311(R) 2005

(picture taken from Science,304, 1079 (2004)„Highlights of the recent literature“)

Charge pumping in Carbon Nanotubes

New J. of Phys. 9, 73 (07)PRB 70, 233401 (04)

I = e·f

1m

SAW and GaN nanowires

Nanotechnology 19 , 275708 (08)

400 nm

SiO2 / Au

GaN

Surface Acoustic Waves and

Semiconductor Nanostructures:

the optic part

Single photon source by bipolar charge transport

GaAs

GaAlAs

GaAs-Quantumwell

Single photon source by bipolar charge transport

PRB 74, 035407 (06)

ZnCdSe/LiNbO3- Hybrid

Epi-Liftoff of ZnCdSe-QWonto LiNbO3 substrate

Finally...

Organic nanofibres

and new stuff

Growth of Carbon Nanosticks

Laser ablation of carbon leads self-organisationof carbon nanosticks->Pyroelectric effects responsible for nanostick growth-> organic nanowire son LiNbO3

p6P nanofibres on LiNbO3

Standard white LiNbO3 Black LiNbO3

p6P nanofibres on LiNbO3

5 µm

5 µm

Post-Growth cleaning withTrimethylpentane

Growth on prestructuredmetal electrodes