Highly efficient Terahertz devices for Nano-Electronics Quantum Technology
PhD open position in the frame of the project STEPforQubits (Short TeraHertz Electrical Pulses for Qubits) funded by the french ANR agency.
Context: The most recent developments of 2D electron gas electronic circuits (2DEG) allow to consider the demonstration of quantum electronic experiments in which a single electron would behave as a single photon emitted in a quantum optical system [1]. However, in such circuits the "coherence length" of an electron is a few tens of microns, which corresponds to a coherence time of a few tens of picoseconds. It is therefore necessary to be able to excite, control and detect a single electron with a temporal accuracy better than one picosecond. For this, we use ultrafast optoelectronics as a technique for generating picosecond electrical pulses that excite electronic circuits. Today, the use of femtosecond lasers makes it possible to generate such pulses with frequency components in the THz range. This technique is often based on GaAs photoconductive switches and is commonly used for experiments in the THz range [2]. However, to our knowledge, it has never been successfully applied to the study of quantum electronic circuits. In this project, we wish to develop a new technological approach for quantum electronics by integrating 2DEG circuits with optoelectronic devices capable of generating picosecond electrical pulses with variable duration and amplitude.
Objectives of the PhD work: The work will focus on the development and experimental characterization of new photoconductive devices based on GaAs technology with high conversion efficiency. The design of this component takes advantage of nano-photonic and plasmonic techniques to increase its efficiency [3]. After evaluation of their performance, the devices will be co-integrated with a 2DEG electronic circuit.
Collaboration and networking: The research will be carried out within the PHOTO group at IMEP-LAHC, Université Savoie Mont-Blanc in Chambéry (http://imep-lahc.grenoble-inp.fr) in collaboration with the QuantECA group at the Neel Institute, CNRS in Grenoble (http://neel.cnrs.fr). Both groups benefit from equipment in high-frequency electronics, lasers, THz benches, cryogenic instrumentation, clean room and nanofabrication lab.
Profile : We are looking to recruit a student with a background in physics, optics or electronics at Master or Engineer level. Electromagnetism, semiconductor physics and optics are at the heart of the proposed subject. A first research experience in one of these fields would be a plus. The candidate should have a strong interest in experimental research and instrumentation.
To apply for this thesis, please send your application (single PDF file). The application should include a cover letter with a brief description of your previous experiences, your CV, a copy of your grades and diplomas from Bac + 3 to Bac + 5.
Thesis start date: September 2020
Contact: Mr. Jean-Francois ROUX,
jean-francois.roux@univ-smb.fr
1] Bauerle et al. 2018 Rep. Prog. Phys. 81 056503 [2] Eusebe et al. 2005 JAP 98, 033711
3] Georgiou et al. ArXiV: 2001.01341