Abstract

Typical quantum gate tomography protocols struggle with a self-consistency problem: the gate operation cannot be reconstructed without knowledge of the initial state and final measurement, but such knowledge cannot be obtained without well-characterized gates. A recently proposed technique, known as randomized benchmarking tomography (RBT), sidesteps this self-consistency problem by designing experiments to be insensitive to preparation and measurement imperfections. We implement this proposal in a superconducting qubit system, using a number of experimental improvements including implementing each of the elements of the Clifford group in single ‘atomic’ pulses and custom control hardware to enable large overhead protocols. We show a robust reconstruction of several single-qubit quantum gates, including a unitary outside the Clifford group. We demonstrate that RBT yields physical gate reconstructions that are consistent with fidelities obtained by randomized benchmarking.

Publication Details
Publication Type
Journal Article
Year of Publication
2015
Volume
17
Number of Pages
113019
DOI
10.1088/1367-2630/17/11/113019
URL
http://arxiv.org/abs/1505.06686
Journal
New Journal of Physics
Contributors
Groups
Date Published
11/2015