TY - JOUR
T1 - Measuring two-qubit gates
AU - White, Andrew G.
AU - Gilchrist, Alexei
AU - Pryde, Geoffrey J.
AU - O'Brien, Jeremy L.
AU - Bremner, Michael J.
AU - Langford, Nathan K.
PY - 2007/1/1
Y1 - 2007/1/1
N2 - Accurate characterization of two-qubit gates will be critical for any realization of quantum computation. We discuss a range of measurements for characterizing two-qubit gates. These measures are architecture-independent and span a range of complexity from simple measurement routines to full quantum-state and process tomography. Simple indicative measures, which flag but do not quantify gate operation in the quantum regime, include the fringe visibility, parity, Bell-state fidelity, and entanglement witnesses. Quantitative measures of gate output states include linear entropy and tangle; measures of, and error bounds to, whole-gate operation are provided by metrics such as process fidelity, process distance, and average gate fidelity. We discuss which measures are appropriate, given the stage of development of the gate, and highlight connections between them.
AB - Accurate characterization of two-qubit gates will be critical for any realization of quantum computation. We discuss a range of measurements for characterizing two-qubit gates. These measures are architecture-independent and span a range of complexity from simple measurement routines to full quantum-state and process tomography. Simple indicative measures, which flag but do not quantify gate operation in the quantum regime, include the fringe visibility, parity, Bell-state fidelity, and entanglement witnesses. Quantitative measures of gate output states include linear entropy and tangle; measures of, and error bounds to, whole-gate operation are provided by metrics such as process fidelity, process distance, and average gate fidelity. We discuss which measures are appropriate, given the stage of development of the gate, and highlight connections between them.
UR - http://www.scopus.com/inward/record.url?scp=33947278275&partnerID=8YFLogxK
U2 - 10.1364/JOSAB.24.000172
DO - 10.1364/JOSAB.24.000172
M3 - Article
AN - SCOPUS:33947278275
SN - 0740-3224
VL - 24
SP - 172
EP - 183
JO - Journal of the Optical Society of America B: Optical Physics
JF - Journal of the Optical Society of America B: Optical Physics
IS - 2
ER -