|Group Leader:||Mohamed Benyoucef|
|PhD Students:||Andrei Kors, Patrick Krawiec, Matusala Yacob, Muhammad Usman|
The research group focuses on the development of novel and advanced quantum architectures fabricated on Si, GaAs, (flat and pre-patterned) and InP substrates using molecular beam epitaxy and investigated their specific aspects of quantum optics. The first is considered to be as one of the key technologies combining the best of both materials leading to a highly versatile hybrid photonics platform which opens the way to large scale photonic integration; this could allow a direct combination of photonics and electronics on the same chip. The later could allow the implementation of efficient single-photon sources for long-distance quantum information.
The emphasis is on the fabrication (growth and processing) and studies the fundamental structural and quantum optical properties of the single quantum nano-architectures. Integration of III-V semiconductor light sources with silicon, fabrication and characterization of microcavities (e.g., photonic crystal) in combination with integrated quantum dots and processing of nanostructured surfaces for optical devices.
- Epitaxy growth of semiconductor nanostructures on different substrates using MBE-system
- Development of single-photon sources at
telecom wavelengths for long-distance quantum communication
- Development of telecom quantum dot
emission for spin storage
- Integration of single InA/GaAs
core-shell quantum dots in silicon
- Processing of nanostructured surfaces
for the realization of deterministic optical devices
- Fabrication and investigation of microcavity
structures (e.g., pillar cavities, photonic crystals)
- Studies the structural properties of
self-assembled quantum dots
- Studies light-matter interaction at the nanoscale of solid-state quantum systems
InP-based quantum dots:
(a) µ-PL spectrum from single InP-based quantum dot (QD). The inset shows the 2x2 µm2 2D AFM image of low density QDs. (b) Single-photon emission at telecom wavelengths from single InP-based QDs (in cooperation with Uni. Stuttgart). (c) Coherent properties of single InP-based QDs (in cooperation with Uni. Paderborn). (d) The measured electron (full squares) and hole (open circles) g-factors for QDs emitting at telecom wavelengths (in cooperation with TU Dortmund).
- S.Gordon, M. Yacob, J. P. Reithmaier, M. Benyoucef, A. Zrenner, “Coherent photocurrent spectroscopy of single InP-based quantum dots in the telecom-band at 1.5 μm”, Appl. Phys. B (2016), DOI 10.1007/s00340-015-6279-6
- V. V. Belykh, A. Greilich, D. R. Yakovlev, M. Yacob, J. P. Reithmaier, M. Benyoucef, and M. Bayer, “Electron and hole g- factors in InAs/InAlGaAs self-assembled quantum dots emitting at telecom wavelengths”, Phys. Rev. B 92, 165307 (2015)
- M. Yacob, J.P. Reithmaier and M. Benyoucef, "Low-density InP-based quantum dots emitting around the 1.5 µm telecom wavelength range", Appl. Phys. Lett. 104, 022113 (2014)
- M. Benyoucef, M. Yacob, J.P. Reithmaier, J. Kettler, P. Michler, "Telecom-wavelength (1.5 µm) single-photon emission from InP-based quantum dots", Appl. Phys. Lett. 103, 162101 (2013)
InP-based photonic crystal microcavities:
(a) μ-PL spectra of L3 PhC microcavity taken at 10 K (blue line) and 300 K (red line). Inset: high-resolution μ-PL spectrum of the fundamental mode M1with quality factor of 8700. (b) µ-PL spectra: black line without polarization, red line with horizontal polarization and blue line with vertical polarization. Insets: SEM image of the L3 PhC cavity and polar plot of cavity modes intensities as a function of polarization angle. (c) µ-PL spectra of a single QD, showing X and XX emission lines. (d) X and XX PL intensities as a function of laser excitation power. (e) X and XX transitions recorded at 0° (red) and 90°(black) polarization angles, showing vanishing fine-structure splitting.
- A. Kors, K. Fucks, M. Yacob, J. P. Reithmaier and M. Benyoucef, “Telecom wavelength emitting single quantum dots coupled to InP-based photonic crystal microcavities", Appl. Phys. Lett.110, 031101 (2017)
Silicon-based quantum dots:
Benyoucef, T. Alzoubi, J.P. Reithmaier, M. Wu, A. Trampert, "Nanostructured
hybrid material based on highly mismatched III-V nanocrystals fully embedded in
silicon", Phys. Stat. Sol. A 211, 817 (2014)
Benyoucef, M. Usman, J.P. Reithmaier, "Bright
light emissions with narrow spectral linewidth from single InAs/GaAs quantum
dots directly grown on silicon substrates", Appl.
Phys. Lett.102, 132101 (2013)
- M. Benyoucef, J.P. Reithmaier, "Direct
growth of III-V quantum dots on silicon substrates: structural and optical
Sci. Technol. 28, 094004 (2013) (invited)
- M. Benyoucef, H-S. Lee, J. Gabel, T. W. Kim, H. L. Park, A. Rastelli and O. G. Schmidt, "Wavelength tunable triggered single-photon source from a single CdTe quantum dot on silicon substrate", Nano Letters 9, 304 (2009)
GaAs-based quantum dots:
Benyoucef, V. Zuerbig, J.P. Reithmaier, T. Kroh, A.W. Schnell, T. Aichele, O.
Benson, "Single-photon emission
from single InGaAs/GaAs quantum dots grown by droplet epitaxy at high
substrates temperature", Nanoscale
Research Letters 7, 493 (2012)
Benyoucef, J.-B. Shim, J. Wiersig, O.G.Schmidt, ''Quality-factor
enhancement of supermodes in coupled microdisks", Opt. Lett. 36, 1317 (2011)
Pfeiffer, K. Lindfors, C. Wolpert, P. Atkinson, M. Benyoucef, A. Rastelli, O.
G. Schmidt, H. Giessen, M. Lippitz, "Enhancing the optical excitation efficiency of a single
self-assembled quantum dot with a plasmonic nanoantenna", Nano Letters 10, 4555 (2010)
- F. Ding, R. Singh, J. D. Plumhof, T.
Zander, V. Křápek, Y. H. Chen, M. Benyoucef, V. Zwiller, K. Dörr, G. Bester, A.
Rastelli, O. G. Schmidt, “Tuning the exciton binding energies in
single self-assembled InGaAs/GaAs quantum dots by piezoelectric-induced biaxial
Rev. Lett. 104, 067405 (2010)
- M. Benyoucef, L. Wang, A. Rastelli, O. G. Schmidt, "Toward quantum interference of photons from independent quantum dots", Appl. Phys. Lett. 95, 261908 (2009)
Site-controlled quantum dots on
pre-patterned GaAs and silicon substrates:
Left: Site-controlled QDs on GaAs substrates. Right: III-V nanostructures localized in the patterned silicon nanoholes.
Usman, J. P. Reithmaier, and M. Benyoucef, “Site-controlled
growth of GaAs nanoislands on pre-patterned silicon substrates” Phys. Stat. Sol. A 212, 443 (2015)
Benyoucef, M. Usman, T. Al-Zoubi, J.P. Reithmaier, "Pre-patterned
silicon substrates for the growth of III-V nanostructures", Phys. Stat. Sol. A 209, 2402 (2012)
- P. Atkinson, S. Kiravittaya, M. Benyoucef, A. Rastelli and O.G. Schmidt, "Site-controlled growth and luminescence of InAs quantum dots using in situ Ga-assisted deoxidation of patterned substrates", Appl. Phys Lett. 93, 101908 (2008)