CQuIC Seminars
Enabling technologies for single electron spin resonance in silicon
Presented by Stephen Carr, SNL
We present the design and development of key technologies that have enabled coherent Rabi oscillations of a single electron spin to be demonstrated at Sandia National Laboratories. A central challenge is delivering a strong microwave magnetic field to the single spin location, which required overcoming detrimental loss and heating along the path from source to qubit nanostructure. This central challenge was addressed through careful microwave design that included three-dimensional electromagnetic field simulation.
The qubit is a single electron spin, which is bound by implanted phosphorus donors in silicon, with the spin state read-out by a nearby single-electron-transistor. An on-chip coplanar stripline terminates in a short-circuit at a microfabricated wire near the single-electron-transistor and donor. The short-circuit current through the microfabricated wire generates a local oscillating magnetic field that is perpendicular to an external static magnetic field of magnitude 1.3 Tesla and drives electron spin resonance at 36.482 GHz. The silicon substrate is mounted to a dilution refrigerator stage with base temperature of 15 mK. Experimental realization of these results required technical solutions to an interesting and challenging cryogenic microwave engineering problem in terms of design, simulation, fabrication, and measurement. If time permits, I will also discuss progress of a joint UNM-SNL effort towards achieving state-of-the-art read-out speed using cryogenic amplification.
Stephen M. Carr
Sandia National Laboratories
Albuquerque, New Mexico
Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.
3:30 pm, Thursday, January 29, 2015
PAIS-2540, PAIS
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