Electrons in silicon have relatively long spin coherence times, motivating research into the use of quantum dots in Si/SiGe as prototype qubits.
The SEM micrograph and schematic at left shows a Si/SiGe double quantum dot used for both single-shot spin measurement and to demonstrate a record figure of merit in a semiconductor charge qubit.
Selected publications on this topic:
“Measurements of capacitive coupling within a quadruple quantum dot array.” S. F. Neyens, E. R. MacQuarrie, J. P. Dodson, J. Corrigan, Nathan Holman, B. Thorgrimsson, M. Palma, T. McJunkin, L. F. Edge, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, Phys. Rev. Applied 12, 064049 (2019). [Journal Article | arXiv]
“The critical role of substrate disorder in valley splitting in Si quantum wells.” S. F. Neyens, R. H. Foote, B. Thorgrimsson, T. J. Knapp, T. McJunkin, L. M. K. Vandersypen, P. Amin, N. K. Thomas, J. S. Clarke, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, Appl. Phys. Lett. 112, 243107 (2018). [Journal Article | arXiv]
“A programmable two-qubit quantum processor in silicon.” T. F. Watson, S. G. J. Philips, E. Kawakami, D. R. Ward, P. Scarlino, M. Veldhorst, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, M. A. Eriksson, and L. M. K. Vandersypen, Nature 555, 633 (2018). [Journal Article | arXiv]
“Extending the coherence of a quantum dot hybrid qubit.” B. Thorgrimsson, Dohun Kim, Yuan-Chi Yang, L. W. Smith, C. B. Simmons, D. R. Ward, R. H. Foote, J. Corrigan, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, npj Quant. Inf. 3, 32 (2017). [Journal Article | arXiv]
“State-conditional coherent charge qubit oscillations in a Si/SiGe quadruple quantum dot.” D. R. Ward, Dohun Kim, D. E. Savage, M. G. Lagally, R. H. Foote, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, npj Quant. Inf. 2, 16032 (2016). [Journal Article | arXiv]
“High-fidelity resonant gating of a silicon-based quantum dot hybrid qubit.” Dohun Kim, D. R. Ward, C. B. Simmons, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, npj Quant. Inf. 1, 15004 (2015). [Journal Article | arXiv]
“Microwave-driven coherent operations of a semiconductor quantum dot charge qubit.” Dohun Kim, D. R. Ward, C. B. Simmons, John King Gamble, R. Blume-Kohout, E. Nielsen, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, Nature Nanotech. 10, 243 (2015). [Journal Article | arXiv]
“Two-axis control of a singlet-triplet qubit with an integrated micromagnet.” X. Wu, D. R. Ward, J. R. Prance, Dohun Kim, John King Gamble, R. T. Mohr, Zhan Shi, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, Proc. Natl. Acad. Sci. 111, 11938 (2014). [Journal Article | arXiv]
“Quantum control and process tomography of a semiconductor quantum dot hybrid qubit.” Dohun Kim, Zhan Shi, C. B. Simmons, D. R. Ward, J. R. Prance, Teck Seng Koh, John King Gamble, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, Nature 511, 70 (2014). [Journal Article | arXiv]
“Fast coherent manipulation of three-electron states in a double quantum dot.” Zhan Shi, C. B. Simmons, D. R. Ward, J. R. Prance, X. Wu, Teck Seng Koh, John King Gamble, D. E. Savage, M. G. Lagally, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, Nature Comm. 5, 3020 (2014). [Journal Article | arXiv]
“Practical design and simulation of silicon-based quantum-dot qubits.” Mark Friesen, P. Rugheimer, D. E. Savage, M. G. Lagally, Daniel W. van der Weide, Robert Joynt, and M. A. Eriksson, Phys. Rev. B 67, 121301 (2003). [Journal Article | arXiv]
“Pseudo-digital quantum bits.” Mark Friesen, Robert Joynt, and M. A. Eriksson, Appl. Phys. Lett. 81, 4619 (2002). [Journal Article]