Scarlino P, van Woerkom D J, Mendes U C, Koski J V, Landig A J, Andersen C K, Gasparinetti S, Reichl C, Wegscheider W, Ensslin K, Ihn T, Blais A, Wallraff A
Department of Physics, ETH Zürich, CH-8093, Zürich, Switzerland.
Institut quantique and Department de Physique, Université de Sherbrooke, Sherbrooke, Québec, J1K 2R1, Canada.
Nat Commun. 2019 Jul 8;10(1):3011. doi: 10.1038/s41467-019-10798-6.
Semiconductor qubits rely on the control of charge and spin degrees of freedom of electrons or holes confined in quantum dots. They constitute a promising approach to quantum information processing, complementary to superconducting qubits. Here, we demonstrate coherent coupling between a superconducting transmon qubit and a semiconductor double quantum dot (DQD) charge qubit mediated by virtual microwave photon excitations in a tunable high-impedance SQUID array resonator acting as a quantum bus. The transmon-charge qubit coherent coupling rate (21 MHz) exceeds the linewidth of both the transmon (0.8 MHz) and the DQD charge qubit (~2.7 MHz). By tuning the qubits into resonance for a controlled amount of time, we observe coherent oscillations between the constituents of this hybrid quantum system. These results enable a new class of experiments exploring the use of two-qubit interactions mediated by microwave photons to create entangled states between semiconductor and superconducting qubits.
半导体量子比特依赖于对限制在量子点中的电子或空穴的电荷和自旋自由度的控制。它们构成了一种很有前景的量子信息处理方法，与超导量子比特互补。在这里，我们展示了在一个用作量子总线的可调谐高阻抗超导量子干涉器件（SQUID）阵列谐振器中，通过虚拟微波光子激发介导的超导transmon量子比特与半导体双量子点（DQD）电荷量子比特之间的相干耦合。transmon-电荷量子比特的相干耦合率（约21兆赫兹）超过了transmon（约0.8兆赫兹）和DQD电荷量子比特（约2.7兆赫兹）两者的线宽。通过将量子比特调谐到共振状态一段可控的时间，我们观察到了这个混合量子系统各组成部分之间的相干振荡。这些结果使得能够开展一类新的实验，探索利用微波光子介导的双量子比特相互作用在半导体和超导量子比特之间创建纠缠态。
