Steffen Matthias, Ansmann M, McDermott R, Katz N, Bialczak Radoslaw C, Lucero Erik, Neeley Matthew, Weig E M, Cleland A N, Martinis John M
Department of Physics and California Nanosystems Institute, University of California, Santa Barbara, CA 93106, USA.
Phys Rev Lett. 2006 Aug 4;97(5):050502. doi: 10.1103/PhysRevLett.97.050502. Epub 2006 Aug 2.
We introduce a new design concept for superconducting phase quantum bits (qubits) in which we explicitly separate the capacitive element from the Josephson tunnel junction for improved qubit performance. The number of two-level systems that couple to the qubit is thereby reduced by an order of magnitude and the measurement fidelity improves to 90%. This improved design enables the first demonstration of quantum state tomography with superconducting qubits using single-shot measurements.
我们引入了一种用于超导相位量子比特（qubit）的新设计概念，其中我们将电容元件与约瑟夫森隧道结明确分开，以提高量子比特的性能。与量子比特耦合的二能级系统数量因此减少了一个数量级，测量保真度提高到了90%。这种改进的设计使得首次能够使用单次测量对超导量子比特进行量子态层析成像演示。
