Randomized Benchmarking of Quantum Gates

Published

January 1, 2007

Author(s)

Emanuel Knill, D. Leibfried, R. Reichle, J. Britton, R. B. Blakestad, J. D. Jost, C. Langer, R Ozeri, Signe Seidelin, David J. Wineland

Abstract

A key requirement for scalable quantum computing is that elementary quantum gates can be implemented with sufficiently low error. One method for determining the error behavior of a gate implementation is to perform process tomography. However, standard process tomography is limited by errors in state preparation, measurement and one-qubit gates. It suffers from inefficient scaling with number of qubits and does not detect adverse error-compounding when gates are composed in long sequences. An additional problem is the fact that desirable error-probabilities for scalable quantum computing are of the order of 0.0001. Experimentally proving such low errors is challenging. We describe a randomized benchmarking method that yields estimates of the computationally relevant errors without relying on accurate state preparation and measurement. Since it involves long sequences of randomly chosen gates, it also verifies that error behavior is stable when used in long computations. We implemented randomized benchmarking on trapped atomic ion qubits, establishing a one-qubit error probability per randomized pi/2 pulse of 0.00482(17). We expect this error probability to be readily improvable.

Citation

Physical Review A (Atomic, Molecular and Optical Physics)

Pub Type

Journals

Keywords

ion traps, quantum computing, quantum errors., quantum gates

Citation

Knill, E. , Leibfried, D. , Reichle, R. , Britton, J. , Blakestad, R. , Jost, J. , Langer, C. , Ozeri, R. , Seidelin, S. and Wineland, D. (2007), Randomized Benchmarking of Quantum Gates, Physical Review A (Atomic, Molecular and Optical Physics) (Accessed October 8, 2025)