Isotope engineering of silicon and diamond for quantum information processing

Prof Kohei M. Itoh
Keio University, Japan
4pm Monday 27 January 2015
Conference Room, 2nd Floor Newton Building, UNSW

Key roles of isotope engineering in silicon and diamond quantum information processing are discussed. While removal of the background 29Si nuclear spins is proven crucial for extending the coherence time of spin qubits in silicon, removal of the background 28Si, 29Si, and 30Si mass fluctuations is also shown to be important for defining the nuclear magnetic resonance frequencies of donors such as 31P in silicon. Effects of removing 13C nuclear spins in diamond are also similar. This talk aims to present an overview of the role of silicon isotope engineering in silicon quantum information processing.
The work has been supported by the Grant-in-Aid for Scientific Research and Project for Developing Innovation Systems by MEXT and the JSPS Core-to-Core Project.

[1] K. M. Itoh and H. Watanabe, "Isotope Engineering of Silicon and Diamond for Quantum Computing and Sensing Applications," MRS Communications, Perspective Article, Open Access,

[2] J. T. Muhonen, J. P. Dehollain, A. Laucht, F. E. Hudson, R. Kalra, T. Sekiguchi, K. M. Itoh, D. N. Jamieson, J. C. McCallum, A. S. Dzurak, and A. Morello, "Storing Quantum Information for 30 Seconds in a Nanoelectronic Device," Nature Nanotechnology 9, 986–991 (2014).

[3] M. Veldhorst, J. C. C. Hwang, C. H. Yang, A. W. Leenstra, B. de Ronde, J. P. Dehollain, J. T. Muhonen, F. E. Hudson, K. M. Itoh, A. Morello, and A. S. Dzurak, "An Addressable Quantum Dot Qubit with Fault-Tolerant Control-Fidelity," Nature Nanotechnology 9, 981–985 (2014).
[4] T. Sekiguchi, A. M. Tyryshkin, S. Tojo, E. Abe, R. Mori, H. Riemann, N. V. Abrosimov, P. Becker, H.-J. Pohl, J. W. Ager, E. E. Haller, M. L. W. Thewalt, J. J. L. Morton, S. A. Lyon, and K. M. Itoh, "Host Isotope Mass Effects on the Hyperfine Interaction of Group-V Donors in Silicon," Phys. Rev. B 90, 121203(R) (2014).