标题： 在开放波导中测量超导量子比特的相干动力学 显示英文标题

标题： Measuring coherent dynamics of a superconducting qubit in an open waveguide

摘要： 我们测量了在无谐振器设置下超导transmon量子比特的退相干和退激速率。 在我们的实验中，量子比特耦合到一个开放的共面波导，使得微波通过该线路的传输取决于量子比特的状态。 为了确定第一个激发态能级的占据情况，我们引入了一种双脉冲技术。 第一个施加的脉冲频率接近量子比特的本征频率，用于激发量子比特。 然后使用第二个脉冲来探测第一个和第二个激发态能级之间的跃迁。 利用这种测量技术可以重建退激动力学和拉比振荡。 此外，我们展示了提取的参数与频域测量对应的估计值之间的一致性。 显示英文摘要

摘要： We measured the relaxation and decoherence rates of a superconducting transmon qubit in a resonator-free setting. In our experiments, the qubit is coupled to an open coplanar waveguide such that the transmission of microwaves through this line depends on the qubit's state. To determine the occupation of the first excited qubit energy level, we introduced a two-pulse technique. The first applied pulse, at a frequency close to the eigenfrequency of the qubit, serves to excite the qubit. A second pulse is then used for probing the transition between the first and second excited energy levels. Utilizing this measurement technique allowed for the reconstruction of the relaxation dynamics and Rabi oscillations. Furthermore, we demonstrate the consistency between the extracted parameters and the corresponding estimations from frequency-domain measurements.