Liles S D, Halverson D J, Wang Z, Shamim A, Eggli R S, Jin I K, Hillier J, Kumar K, Vorreiter I, Rendell M J, Huang J Y, Escott C C, Hudson F E, Lim W H, Culcer D, Dzurak A S, Hamilton A R
School of Physics, University of New South Wales, Sydney, NSW, 2052, Australia.
Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056, Basel, Switzerland.
Nat Commun. 2024 Sep 3;15(1):7690. doi: 10.1038/s41467-024-51902-9.
Holes in silicon quantum dots are promising for spin qubit applications due to the strong intrinsic spin-orbit coupling. The spin-orbit coupling produces complex hole-spin dynamics, providing opportunities to further optimise spin qubits. Here, we demonstrate a singlet-triplet qubit using hole states in a planar metal-oxide-semiconductor double quantum dot. We demonstrate rapid qubit control with singlet-triplet oscillations up to 400 MHz. The qubit exhibits promising coherence, with a maximum dephasing time of 600 ns, which is enhanced to 1.3 μs using refocusing techniques. We investigate the magnetic field anisotropy of the eigenstates, and determine a magnetic field orientation to improve the qubit initialisation fidelity. These results present a step forward for spin qubit technology, by implementing a high quality singlet-triplet hole-spin qubit in planar architecture suitable for scaling up to 2D arrays of coupled qubits.
由于强大的固有自旋 - 轨道耦合，硅量子点中的空穴在自旋量子比特应用方面很有前景。自旋 - 轨道耦合产生复杂的空穴自旋动力学，为进一步优化自旋量子比特提供了机会。在此，我们展示了一种利用平面金属氧化物半导体双量子点中的空穴态的单重态 - 三重态量子比特。我们展示了高达400 MHz的单重态 - 三重态振荡的快速量子比特控制。该量子比特表现出良好的相干性，最大退相时间为600 ns，使用重聚焦技术可将其提高到1.3 μs。我们研究了本征态的磁场各向异性，并确定了一个磁场方向以提高量子比特初始化保真度。这些结果通过在适合扩展到耦合量子比特二维阵列的平面架构中实现高质量的单重态 - 三重态空穴自旋量子比特，为自旋量子比特技术向前迈进了一步。
