Southwest Quantum Information and Technology

Full controllability of a singlet-triplet qubit coupled to a nuclear spin qubit

Presenting Author: John Gamble, Center for Computing Research, Sandia National Laboratories
Contributing Author(s): Andrew D. Baczewski, N. Tobias Jacobson, Richard P. Muller, Erik Nielsen, Patrick Harvey-Collard, M. S. Carroll

Two promising candidates for qubits in semiconductor devices are the nuclear spin of an impurity atom and the spin of small collections of isolated electrons. In conventional schemes, nuclear spins tend to have exceptional coherence properties, with decoherence times ranging from minutes to hours. On the other hand, electronic encodings are more readily manipulated, but suffer shorter decoherence times. In this work, we show how to leverage the best features of both approaches by achieving full two-qubit control over the hybrid system comprising a singlet-triplet electronic qubit coupled to a nuclear spin qubit. Building on recent experiments at Sandia, we demonstrate through numerical simulation that this two-qubit system is both operationally flexible and practically accessible with current technology. We conclude by assessing the expected qubit performance of both radio frequency and pulsed-gate operation under realistic experimental conditions. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Security Administration under contract DE-AC04-94AL85000.

(Session 5 : Thursday from 5:00 - 7:00 pm)