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Reference : UPR10-MICPEF-008
Workplace : VALBONNE
Date of publication : Friday, August 02, 2019
Scientific Responsible name : Jesus ZUNIGA PEREZ
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 1 October 2019
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
Single photons are the backbone of many quantum information technologies including quantum computation, quantum information processing and especially quantum communications, where photons are used as flying qubits between nodes of a large quantum network. Since in these architectures we aim for long communications distances, the ideal operation wavelengths happen to be those compatible with low-loss optical fibers (i.e. at telecommunication wavelengths).
Currently, many of these demonstrations are carried out using heralded single photon sources based on parametric downconversion. However, these sources are extremely attenuated limiting thereby the achievable communication rate. In this context, solid state sources based on quantum dots or structural defects in semiconductor matrices appear as ideal candidates. However, the shallow carrier confinement in arsenide-based quantum dots limits their operation temperature to cryogenic ones and, besides, while single-photon emitters have been obtained at telecom wavelengths, their figures of merit are far from their infrared counterparts. An alternative approach consists in exploiting efficient single-photon emitters in the infrared and by frequency downconversion transpose the produced single photons to the desired wavelengths. And even if conversion efficiencies as large as 40% have been demonstrated, the necessary set-ups are too bulky.
In the current PhD we propose to study the design, fabrication and characterization of a new single-photon source emitting at telecom wavelengths, operating at room-temperature and compatible with silicon photonics. Such a source is found in GaN, a widespread semiconductor with a mature technology. This source was first characterized thoroughly by Nanyang Technological University, who will be an active partner of the current PhD. Overall, the PhD aims at developing the full potential of the new single-photon source, its integration into nitrides-based optical microcavities and waveguides and, in fine, its electrical injection.
• The PhD candidate will integrate the Nanotechnology Team of CRHEA and will be under the supervision of Dr. J. Zuniga-Perez. Due to the collaborative nature of the current project, the PhD candidate will spend several months at NTU Singapore contributing to further quantum optical characterization of the sources.
• Expertise on Materials Science and/or Optics is expected from candidates.
The Research Center for Heteroepitaxy and its Applications (CRHEA - UPR10) is a CNRS research laboratory specializing in the epitaxy of large bandgap semiconductor materials such as III nitride materials (GaN, AlN), zinc oxide (ZnO), silicon carbide (SiC) and their micro- and nanofabrication in a clean room. CRHEA also studies 2D materials such as graphene, or boron nitride.
The main areas covered by the CRHEA concern the energy transition, the communications of the future, the environment and health. CRHEA also conducts fundamental studies in nanoscience and crystal growth.
High energy bandgap materials are key elements for power electronics, ultra-high frequency electronics, LED-based lighting and new generations of micro-displays. CRHEA visible and ultraviolet light sources have multiple applications for lighting, biophotonics and water purification. CRHEA also develops components in the THz domain, photonic circuits, advanced optical components based on metasurfaces, spintronic applications, sensors and is involved in the development of quantum technologies.
The laboratory has eight molecular beam epitaxy growth reactors and six vapor phase growth reactors. It also has tools for structural characterization of materials and a clean room for micro and nanofabrication.
The candidate will carry out his research activity within the NANO group (9 researchers and engineers and a dozen doctoral and postdoctoral fellowships).
The combination of top-down and bottom-up approaches makes it possible to exploit all the possibilities offered by nanostructures and this is the strength of the Nanotechnologies team, which uses GaN and ZnO as materials of choice. Our interests range from basic materials science, including MBE and MOCVD growth to new materials (eg ZnMnO, rare earth nitrides and oxynitrides), to the development of more complex nanophotonic systems. These include metasurfaces, which allow the manufacture of ultrathin-ultralight optoelectronic components such as metal lenses, optical microcavities. These are the ideal playground for testing effects in quantum electrodynamics and obtaining Bose-Einstein condensates in a semiconductor environment. Finally, a nanophotonic platform based on GaN nanowires is able to stimulate biological cells with unprecedented spatial resolution. In addition, the manipulation of the spin of carriers and / or excitons within these photonic structures, thanks to our magnetic materials, opens the possibility of coupling spin and photons in an electrically addressable interface.
Constraints and risks
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