A post-doctoral position is opened at the Interdisciplinary Research Institute of Grenoble (IRIG, formerly INAC) of the CEA Grenoble (France) on the theory and modeling of arrays of silicon-on-insulator quantum bits (qubits). This position fits into an ERC Synergy project, quCube, aimed at developing two-dimensional arrays of such qubits. The selected candidate is expected to start between October and December 2019, for up to three years. For more information, see below or http://www.cea.fr/drf/irig/Documents/Post-doc/2019_Postdoc_L_Sim.pdf

Quantum information technologies on silicon have raised an increasing interest over the last few years [1]. Indeed, record coherence times have been achieved in 28Si samples [2]; also, silicon benefits from the exceptional know-how developed for conventional micro-electronics, and is the natural platform for the co-integration of quantum bits (qubits) with the classical circuitry needed to drive them.

Grenoble is pushing forward an original platform based on the “silicon-on-insulator” (SOI) technology. The information is stored in the spin of carrier(s) trapped in quantum dots, which are etched in a thin silicon film and are controlled by metal gates. On this SOI platform, CEA has for example demonstrated the first hole spin qubit [3], and the electrical manipulation of a single electron spin [4]. Grenoble is now heading toward the demonstration of multi-qubit gates on SOI, and has received in 2018 an ERC Synergy grant with the aim to develop two-dimensional arrays of SOI qubits. This large project is lead by a consortium gathering three of the main laboratories of Grenoble, CEA/LETI, CEA/IRIG and CNRS/Néel.

Many aspects of the physics of silicon qubits are still poorly understood, so that it is essential to support the experimental activity with state-of-the-art modeling. For that purpose, CEA is actively developing the “TB_Sim” code. TB_Sim relies on atomistic tight-binding and multi-bands k.p descriptions of the electronic structure of materials and includes, in particular, a time-dependent configuration interaction solver for the dynamics of interacting qubits. Using TB_Sim, CEA has recently investigated various aspects of the physics of SOI qubits, in tight collaboration with the experimental teams in Grenoble and the partners of CEA in Europe [4-8].

The aims of this post-doctoral position are, therefore, to improve our understanding of the physics of these devices and optimize their design, and, in particular,

• To model spin manipulation, readout, and coherence in one- and two-dimensional arrays of SOI qubits.
• To model exchange interactions in these arrays and assess the operation of multi-qubit gates.

This work will be strongly coupled to the experimental activity in Grenoble. The candidate will have access to experimental data on state-of-the-art devices.

The candidate should send her/his CV to Yann-Michel Niquet (yniquet@cea.fr), with a list of publications, a motivation letter with a summary of past accomplishments, and contact details of two persons for recommendation letters.

References:
[1] Embracing the quantum limit in silicon computing,
J. J. L. Morton, D. R. McCamey, M. A. Eriksson and S. A. Lyon,
Nature 479, 435 (2011).
[2] Electron spin coherence exceeding seconds in high-purity silicon,
A. M. Tyryshkin, S. Tojo, J. J. L. Morton, H. Riemann, N. V. Abrosimov, P. Becker, J.-J. Pohl, T. Schenkel, M. L. W. Thewalt, K. M. Itoh and S. A. Lyon,
Nature Materials 11, 143 (2012).
[3] A CMOS silicon spin qubit,
R. Maurand, X. Jehl, D. Kotekar-Patil, A. Corna, H. Bohuslavskyi, R. Laviéville, L. Hutin, S. Barraud, M. Vinet, M. Sanquer and S. de Franceschi,
Nature Communications 7, 13575 (2016).
[4] Electrically driven electron spin resonance mediated by spin–valley–orbit coupling in a silicon quantum dot,
A. Corna, L. Bourdet, R. Maurand, A. Crippa, D. Kotekar-Patil, H. Bohuslavskyi, R. Laviéville, L. Hutin, S. Barraud, X. Jehl, M. Vinet, S. de Franceschi, Y.-M. Niquet and M. Sanquer,
npj Quantum Information 4, 6 (2018).
[5] All-electrical manipulation of silicon spin qubits with tunable spin-valley mixing,
L. Bourdet and Y.-M. Niquet,
Physical Review B 97, 155433 (2018).
[6] Electrical spin driving by g-matrix modulation in spin-orbit qubits,
A. Crippa, R. Maurand, L. Bourdet, D. Kotekar-Patil, A. Amisse, X. Jehl, M. Sanquer, R. Laviéville, H. Bohuslavskyi, L. Hutin, S. Barraud, M. Vinet, Y.-M. Niquet and S. de Franceschi,
Physical Review Letters 120, 137702 (2018).
[7] Electrical manipulation of semiconductor spin qubits within the g-matrix formalism,
B. Venitucci, L. Bourdet, D. Pouzada and Y.-M. Niquet,
Physical Review B 98, 155319 (2018).
[8] Simple model for electrical hole spin manipulation in semiconductor quantum dots: Impact of dot material and orientation,
B. Venitucci and Y.-M. Niquet,
Physical Review B 99, 115317 (2019).

Additional informations about the laboratory:
http://www.cea.fr/drf/IRIG/english/Pages/Presentation.aspx
http://www.researchgate.net/profile/Yann-Michel_Niquet
http://scholar.google.fr/citations?user=h02ymwoAAAAJ

More about Grenoble and its surroundings:
http://www.isere-tourism.com/