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PhD offer: Coupling of SiC color centers to nanophotonic structures

University of registration : Ecole Centrale de Lyon, RMIT
Doctoral School :
Speciality: Nanomaterials / Photonics
PhD title: Coupling of SiC color centers to nanophotonic structures
Research unit : INL, UMR5270 / RMIT
Thesis Directors : Xavier Letartre (INL, France), Stefania Castelletto (RMIT, Australia)
Co-supervisor : Jean-Marie Bluet

Funding type: COFUND Marie Slodowska Curie Action

This project is under the Marie Skłodowska-Curie Actions (MSCA) program. There are no nationality conditions but the candidates must fulfill the MSCA mobility conditions, which means that she/he must not have stayed more than 1 year in France during the last 3 years immediately before the call deadline (31/05/2019)

Expected start date: 01/10/2019

Contacts:

Prof. Jean-Marie Bluet
Jean-marie.bluet@insa-lyon.fr
tel: +33 4 72 43 87 32

Ass. Pr. Stefania Castelletto
stefania.castelletto@rmit.edu.au

websites:

Collaborations/External partners:
Dr Matteo Bosi (IMEM-CNR): Chemical vapor deposition of 3C SiC on Silicon
IPNL-Lyon: proton irradiation

Domain and scientific context:
Point-like defects in wide-bandgap materials are attracting intensive research attention owing to prospective applications in quantum technologies (information processing, sensing) and in near infrared spectrum bio-imaging. The reason is three-fold: (i) these defects can be considered as artificial atoms with highly efficient optical transitions (single photon sources realization); (ii) they may encompass charge, orbital and spin degrees of freedom, with possibility for instance of optical control of the spin (Qubit application); (iii) the spin and electronic states can be well isolated from environmental fluctuations leading to record spin coherence. In this context, the nitrogen-vacancy (NV) center in diamond has become a highly mature system, used for a large range of applications. Nevertheless, since 2010, point defects in SiC have been intensively studied. Indeed, SiC presents advantages for these applications: (i) growth at an industrial scale ; (ii) control of the technological steps for devices realization thanks to the upstream of power electronic applications ; (iii) unparalleled properties making SiC an ideal platform for photonic quantum information processing.

Keywords: Point Like defects – nanopillars – single photon source – nanophotonics – optical spectroscopy

Objectives:

The goal of the thesis is to realize and characterize SiC photonics structures (nanopillars, photonic crystals (PhC) cavities) with embedded color centers (Si vacancy (VSi) and Nitrogen – carbon vacancy complex (NCVSi)).  The enhancement of photoluminescence (PL) emission both by collection efficiency improvement and/or spontaneous emission rate increase (Purcell effect) will be evaluated and will allow for characterization of optical spin control (Optically Detected Magnetic Resonance experiment) at single defect level. The expected demonstration of the optical spin-control in these structures will allow to use them as building block for applications in integrated quantum nanophotonics circuits. These circuits can be used for quantum sensing and quantum network applications.

Scientific challenges:

Technological challenges:

  • On demand realization of color centers : localization of color center in nanopillars or PhC cavities by mean of proton irradiation and masking (INL) ; Focused ion Beam writing (INL-RMIT) ; femtosecond laser writing (RMIT)
  • Optimisation of PL enhancement: Design of nanopillar shape (tapering for instance) by control of deep dry etching (ICP-RIE) parameters. Design of PhC cavities for high Purcell effect.

Characterization challenges :

  • Optical spin state manipulation at single defect level: Benefit of  the enhancement of the emission obtained in the nanopillars for magnetic sensing and nanoscopy. Realize micro-ODMR experiment via the use of an N-STORM microscope available at MNRF facility.
  • Extend recently established super-resolution methods used for NV centers in diamond to  color centers in SiC for super-resolution in biological systems.

Expected original contributions:

Taking up the above mentioned challenges will lead to optimization of VSi and NCVSi magneto-optical properties and will allow coherent manipulation, measurement and entanglement using optical fields. Based on single NCVSi and VSi center, we will work towards the formation of spin-photon entanglement state, which is an essential part towards quantum network and distributed quantum computation.

Research program and methodology:

The project will be benefit from initial collaborative studies started between INL and RMIT. Indeed, a process for nanopillars realization has been developed at INL and the optical characterization of a first batch is ongoing at RMIT.

First year: Optimisation of nanopillars process (nanolyon platform) ; simulation for PhC cavities design (INL-ECL), color center realization (Protons at IPNL, Laser writing at RMIT).  Optical characterization (collective INL, single RMIT). 9 month at INL 3 at RMIT.

Second year: Magneto-optical characterization at RMIT (N-Storm Microscope from MNRF) ; PhC cavities realization and characterization (INL, Nanolyon platform) and color center realization ; new nanopillar sample realization. 3 month at RMIT, 9 at INL.

Third year: Optical and magneto optical characterization at RMIT at single defect level, super-resolution in biological systems RMIT,  results valorisation and thesis writing at INL. 6 month   at RMIT, 6 month at INL.

Nanolyon platform will be intensively used for the technological development of the samples: nanopillars and PhC cavities. Laser and e-beam lithography will be used. Dry etching process, both RIE for PhC and deep RIE (ICP-RIE) for nanopillars design will be developed based on our knowledge for power electronic devices (MESA, trench insulation).

MNRF facility will be necessary for the use of the NSTORM microscope equipped with radio-frequency excitation and magnetic field modulation and also expertise in biological systems such as PC2 mammalian cell laboratory for the super-resolution experiment in biological systems. Additionally, MNRF will be heavily used for other tasks that require sample optimization/refinement such as annealing and micro/nano fabrication, wet etching (surfaced cleaning) and analytical characterization based on AFM.

As mentioned in the research program, the project will covers different fields: nanotechnology, nanomaterials and photonics. It will require development of skills in (i) technological realization in clean room, (ii) numerical simulation for structure design and (iii) optical + magneto-optical characterization.

Scientific supervision:

  • Description of the supervision committee :
Name, First name  Laboratory/Team  Scientific skills Percentage of supervision
Letartre, Xavier INL/ECL Photonics 20%
Castelletto, Stefania RMIT Point defect spectroscopy 40%
Bluet, Jean-Marie RMIT SiC technology and spectroscopy 40%
  • Integration inside the laboratories (percentage of working time inside these laboratories) : 67% at INL, 33% at RMIT

PhD funding: Co-Fund Marie Sladowska Curie Action (MSCA) ECL/RMIT (ECLAUsion program)

Profile of the candidate: Master degree in the field of nanoscience or nanomaterials with knowledge in quantum photonics.

Objectives for the valorization of the research work: Results will be published in high impact international journals and presented at international conferences.

Skills that will be developed during the PhD: work in clean room facilities, cutting edge spectroscopy, internationals collaboration, project management.

Professional opportunities after the PhD: Quantum technologies are on the rise at the academic (national programs IN USA, UK, flagship in Europe …) and industrial level (Google, HP …). This PhD with the international and interdisciplinary dimensions it covers will lead to opportunities in academic research careers and also in the industry.

Bibliographic references about the PhD topic:

A recent review paper Authored by one of the Supervisor, Prof S. Castelletto, is an excellent first reading to have an overview at the beginning.

  • Lohrmann, A, Johnson, BC, McCallum, JC & Castelletto, S 2017, ‘A review on single photon sources in silicon carbide’, Reports onProgress in Physics, vol. 80, no. 3Next, many references there in will be interesting for deepening.