Optically Driven Spin Based Quantum Dots for Quantum Computing

摘要

This program conducted experimental and theoretical research aimed at developing an optically driven quantum dot quantum computer. In addition to the two co-principal investigators (Sham and Steel), the work was done in collaboration with Dan Gammon at the Naval Research Laboratory. D. Gammon had responsibility for designing, fabricating and basic spectroscopy of the material, LJ Sham is responsible for theoretical support and concept development, and DG Steel is responsible for experimental demonstration of key experimental demonstrations for quantum computing. For this program, qubit is the spin of the electron trapped in a self-assembled quantum dot in InAs. Optical manipulation using the trion state allows for fast (psec) rotations of the electron spin. The program achieved several milestones including demonstration of initialization, fast spin rotations and a phase gate, reduction of nuclear fluctuations extending the spin coherence time by 3 orders of magnitude, major advances in scalable gate proposals, and two proposals for measurement of measurement of true spin coherence time.