Modeling silicon-on-insulator quantum bit arrays

Job type: 

Application deadline: 

Wednesday, July 31, 2019

Research group: 

CEA, Institute for Nanosciences and Cryogenics

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

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 (, with a list of publications, a motivation letter with a summary of past accomplishments, and contact details of two persons for recommendation letters.

[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).

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