Photonics and Semiconductor Nanophysics

Paul Koenraad, Andrea Fiore, Erik Bakkers & Jaime Gomez-Rivas

M

aterials

D e v i c e s S y s t

e m

s

COBRA Inter-University Research Institute on Communication

Technology

PSN group

Where do you find semiconductors?

Why are semiconductors important?

Most energy efficient illumination sources

Most efficient photovoltaic material

Basic material for electronics industry

Basic material for Information and Communication Technology (ICT)

PSN RESEARCH

Goal: Achieve ultimate control in the structural, thermal, mechanical, electrical and photonic properties of semiconductor nanostructures

Physics of semiconductor nano-objects (3D/2D/1D/0D) Individual nanostructures and doping atoms Utilize quantum effects in nano-objects

Single photons/single electrons/single spins

GaAs substrate

AlAsGaAs

Be doped AlAs

GaAs

Si doped AlAsGaAs

AlAs

How do we make semiconductors

Nanometer sized in all 3 directions and controlled incorporation of doping atoms

Growth Research

500 nm * 500 nm

Self-assembled InAs quantum dots on GaAs

Atomic Force Microscopy image

Different semiconductor materials:• IV: Si, Ge• III-V: GaAs, InP, etc.• II-VI: ZnO, CdSe, etc.

Semiconductor nanowires

Characterization of NanostructuresScanning Tunneling Microscopy image

Atom Probe Tomography image

Indium atomsGallium atoms

Characterization of semiconductors

0.5 1.0 1.5

0.0

0.1

0.2

0.3

0.4

0.5

Ext

inct

ion

Frequency (THz)

0 mJ /cm-2

0.7 mJ /cm-2

1.4 mJ /cm-2

2.8 mJ /cm-2

N <1015 cm-3

N 1018 cm-3

= 400 l nm

Photonic devices: single-photons

Quantum dots emit single photons:

10 nm

Jin, ... Fiore, Nature Nano. 2014Pagliano, ..., Fiore, Nature Comm. 2014

• Applications: Quantum information processing• Fundamental science: How light is bornExample: Ultrafast control of spontaneous emission Nano-opto-electro-

mechanical systems

Photonic devices: many photons

Plasmonic LEDs and lasers Nanowire solar cells

Example internship projectJeroen Schouwenberg, 2012: Modeling and design of photonic crystal filters

PSN interns participate to real research projects

Milo Swinkels (Master internship 2014): Ultrafast control of cavity QED

Tommy Barten (Master internship 2014): Nanowire absorption

What can you do?Nanowire Growth (Erik Bakkers)Nanowire Devices (Erik Bakkers)Characterization (Paul Koenraad)Single Impurities (Paul Koenraad)Optical spectroscopy (Paul Koenraad)Plasmonics (Jaime Gomez-Rivas)THz physics (Jaime Gomez-Rivas)Single Photons (Andrea Fiore)Quantum Optics (Andrea Fiore)Photonic Devices (Andrea Fiore)

Come and visit us, you are most welcome !Secretariaat.psn@tue.nl