State tomography of capacitively shunted phase qubits with high fidelity.
نویسندگان
چکیده
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.
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عنوان ژورنال:
- Physical review letters
دوره 97 5 شماره
صفحات -
تاریخ انتشار 2006