US 12,288,127 B2
Efficient synthesis of optimal multi-qubit Clifford circuits
Sergey Bravyi, Ossining, NY (US); Joseph Latone, San Francisco, CA (US); and Dmitri Maslov, New Canaan, CT (US)
Assigned to INTERNATIONAL BUSINESS MACHINES CORPORATION, Armonk, NY (US)
Filed by International Business Machines Corporation, Armonk, NY (US)
Filed on Oct. 9, 2020, as Appl. No. 17/066,916.
Prior Publication US 2022/0114468 A1, Apr. 14, 2022
Int. Cl. G06N 10/00 (2022.01); G06F 7/76 (2006.01); G06F 17/16 (2006.01)
CPC G06N 10/00 (2019.01) [G06F 7/76 (2013.01); G06F 17/16 (2013.01)] 15 Claims
OG exemplary drawing
 
6. A computer-implemented method, comprising:
receiving, by a device operatively coupled to a processor, as input a number n representing a quantity of qubits; and
generating, by the device and via a cost-invariant reduction function, as output a library of different n-qubit canonical representatives that respectively correspond to different cost-invariant equivalence classes of n-qubit Clifford group elements, wherein the cost-invariant equivalence classes are classes that are equivalent in terms of entangling-gate cost;
receiving, by the device, as input a suboptimal n-qubit Clifford operator;
computing, by the device, the cost of the suboptimal n-qubit Clifford operator; and
searching, by the device, the library of n-qubit canonical representatives and determining or identifying an optimal n-qubit Clifford operator that implements the suboptimal n-qubit Clifford operator and is lower cost than the cost of the suboptimal n-qubit Clifford operator.