A silicon metal-oxide-semiconductor electron spin-orbit qubit

作者：Jock Ryan M; Jacobson N Tobias; Harvey Collard Patrick; Mounce Andrew M; Srinivasa Vanita; Ward Dan R; Anderson John; Manginell Ron; Wendt Joel R; Rudolph Martin; Pluym Tammy; Gamble John King; Baczewski Andrew D; Witzel Wayne M; Carroll Malcolm S^*

来源：Nature Communications, 2018, 9(1): 1768.

DOI：10.1038/s41467-018-04200-0

The silicon metal-oxide-semiconductor (MOS) material system is a technologically important implementation of spin-based quantum information processing. However, the MOS interface is imperfect leading to concerns about 1/f trap noise and variability in the electron g-factor due to spin-orbit (SO) effects. Here we advantageously use interface-SO coupling for a critical control axis in a double-quantum-dot singlet-triplet qubit. The magnetic field-orientation dependence of the g-factors is consistent with Rashba and Dresselhaus interface-SO contributions. The resulting all-electrical, two-axis control is also used to probe the MOS interface noise. The measured inhomogeneous dephasing time, T-2m*, of 1.6 mu s is consistent with 99.95% Si-28 enrichment. Furthermore, when tuned to be sensitive to exchange fluctuations, a quasi-static charge noise detuning variance of 2 mu eV is observed, competitive with low-noise reports in other semiconductor qubits. This work, therefore, demonstrates that the MOS interface inherently provides properties for two-axis qubit control, while not increasing noise relative to other material choices.

• 出版日期2018-5-2