Practical scheme for quantum computation with any two-qubit entangling gate.
Which gates are universal for quantum computation? Although it is well known that certain gates on two-level quantum systems (qubits), such as the controlled-not, are universal when assisted by arbitrary one-qubit gates, it has only recently become clear precisely what class of two-qubit gates is universal in this sense. We present an elementary proof that any entangling two-qubit gate is universal for quantum computation, when assisted by one-qubit gates. A proof of this result for systems of arbitrary finite dimension has been provided by Brylinski and Brylinski; however, their proof relies on a long argument using advanced mathematics. In contrast, our proof provides a simple constructive procedure which is close to optimal and experimentally practical.
Bremner
Michael J
MJ
Centre for Quantum Computer Technology and Department of Physics, The University of Queensland, QLD 4072, Australia.
Dawson
Christopher M
CM
Dodd
Jennifer L
JL
Gilchrist
Alexei
A
Harrow
Aram W
AW
Mortimer
Duncan
D
Nielsen
Michael A
MA
Osborne
Tobias J
TJ