Gigahertz single-photon sources using coupled quantum wires and dots in microcavities

Research Topic

A surface acoustic wave (SAW) can efficiently enhance the recombination lifetime and thereby the transport length of photo-excited electron-hole pairs along a semiconducting surface. The efficiency of the carrier transport, and in particular of the spin transport, can be enhanced by confining the carriers in quantum wires. This project aims at the study of charge and spin transport in quantum wire structures for quantum functionalities.


Goals

The main goal of the project is the creation of a single-photon source, based on sidewall quantum wires on GaAs(001) substrates. In order to define the polarization of the emitted photon, we include SAW-driven transport of charge and spin carriers in the quantum wire. The single-photon source is fabricated using photolithographically patterned GaAs (001) substrates, on which the anisotropic overgrowth of a quantum well by MBE results in the formation of quantum wires on the sidewalls of patterns along the [110] crystal direction. Recently, we observed acoustic transport of both charge and spins over tens of microns in the quantum wire. It was shown that potential fluctuations along the transport path disturb the acoustic transport. However, these fluctuations can possibly also act as single-photon emitters. Finally, a microcavity will be included in order to further enhance the source efficiency. A first device constituted part of the milestone MS11 (emission from regrown samples). It is anticipated that the milestone will be completed by month 48.

Fellow

Paul L. J. Helgers

Host: Paul-Drude-Institut für Festkörperelektronik Berlin

Scientific Background

During my studies in Applied Physics (attended at Eindhoven University of Technology, Netherlands), I got mainly fascinated by quantum physics and I chose to specialize in solid state physics. This resulted in the completion of the master ‘Applied Physics – Functional Materials & Nanotechnology’ in 2015. Throughout my studies I was involved in various research projects in the fields of semiconductor physics and spintronics, and I conducted an internship abroad (Universidade de São Paulo, Brazil) to gain experience in working and living in a different culture. During my project within the SAWtrain network, I lived and worked for six months in Japan, where I conducted part of my experiments at NTT Basic Research Labs. Continuing my research within the SAWtrain network, I am expanding my skills and knowledge in the field of solid state physics, semiconductor fabrication and especially in optical experiments.

2019
Conference/Workshop Contributions
    • Acoustic spin transport in planar GaAs quantum wires
      P. L. J. Helgers, K. Biermann, H. Sanada, Y. Kunihashi, P. V. Santos
      Spring Meeting of the German Physical Society (DPG) (Regensburg, Germany, March 31 – April 5, 2019)
2018
Conference/Workshop Contributions
    • Long-range acoustic carrier transport in quantum wires on GaAs (001)
      P. L. J. Helgers, K. Biermann, H. Sanada, Y. Kunihashi, P. V. Santos
      International Workshop on Sound-enabled Nanotechnologies (Valencia, Spain, November 26 – 29, 2018)
    • Acoustic charge and electron-spin transport in GaAs quantum wires
      P. L. J. Helgers, K. Biermann, H. Sanada, Y. Kunihashi, P. V. Santos
      34th International conference on the physics of semiconductors (Montpellier, France, July 29 – August 3, 2018)
    • Acoustic charge and electron-spin transport in GaAs quantum wires
      P. L. J. Helgers, K. Biermann, H. Sanada, Y. Kunihashi, P. V. Santos
      1st International Symposium on “Single Photon based Quantum Technologies” (Berlin, Germany, May 30 – June 1, 2018)
    • Confined microcavity polaritons: effect of trap geometry on potential shape
      A. Kuznetsov, P. L. J. Helgers, K. Biermann, P. V. Santos
      Spring Meeting of the German Physical Society (DPG) (Berlin, Germany, March 11-16, 2018)
    • Acoustic charge and electron-spin transport in GaAs quantum wires
      P. L. J. Helgers, K. Biermann, H. Sanada, Y. Kunihashi, P. V. Santos
      Spring Meeting of the German Physical Society (DPG) (Berlin, Germany, March 11-16, 2018)
2017
Conference/Workshop Contributions
    • Acoustically driven single-photon sources
      P. L. J. Helgers, K. Biermann, H. Sanada, Y. Kunihashi, P. V. Santos
      8th International school and symposium on nanoscale transport and photonics (Atsugi, Japan, November 13-17, 2017)
    • Acoustic modulated single-photon sources
      P. L. J. Helgers, K. Biermann, P. V. Santos
      SAWtrain Summer School: Physics and applications of GHz vibrations in semiconductors (Cargèse, France, July 11-21, 2017) | Internal
    • Confined exciton- polaritons in a laterally structured (Al,Ga)As microcavity
      K. Biermann, A. S. Kuznetsov, P. L. J. Helgers, A. Tahraoui, P. V. Santos
      19th European Workshop on Molecular Beam Epitaxy (Korobitsyno, Russia, March 19-22, 2017) | Internal
    • Exciton-polaritons in a laterally structured GaAs(001) based microcavity
      K. Biermann, P. L. J. Helgers, A. S. Kuznetsov, A. Tahraoui, P. V. Santos
      19th European Workshop on Molecular Beam Epitaxy (Korobitsyno, Russia, March 19-22, 2017) | Internal
    • Optical confinement and conversion of exciton polaritons in a structured (Al,Ga)As microcavity
      A. S. Kuznetsov, P. L. J. Helgers, K. Biermann, P. V. Santos
      Spring Meeting of the German Physical Society (DPG) (Dresden, Germany, March 19-24, 2017) | Internal
2016
Conference/Workshop Contributions
    • Confined exciton-polaritons in structured (Al,Ga)As micro-cavities
      A. Kuznetsov, P. L. J. Helgers, K. Biermann, P. V. Santos
      German-Japanese meeting on the science of hybrid quantum systems (Berlin, Germany, November 10-11, 2016)