US 12,014,247 B2
Systems and methods for compressed sensing measurement of long-range correlated noise
Seyed Alireza Seif Tabrizi, Adelphi, MD (US); Mohammad Hafezi, Washington, DC (US); and Yi-Kai Liu, Gaithersburg, MD (US)
Assigned to University of Maryland, College Park, College Park, MD (US); and Government of the United States of America, As Represented by the Secretary of Commerce, Gaithersburg, MD (US)
Filed by University of Maryland, College Park, College Park, MD (US); and Government of the United States of America, as Represented by the Secretary of Commerce, Gaithersburg, MD (US)
Filed on May 13, 2022, as Appl. No. 17/743,850.
Claims priority of provisional application 63/188,373, filed on May 13, 2021.
Prior Publication US 2023/0058207 A1, Feb. 23, 2023
Int. Cl. G06N 10/70 (2022.01)
CPC G06N 10/70 (2022.01) 17 Claims
OG exemplary drawing
 
1. A computer-implemented method for detecting a two-qubit correlated dephasing error, the method comprising:
accessing a signal of a quantum device, the quantum device including a plurality of qubits, wherein every qubit has a nonzero rate of dephasing, wherein some qubits have a nonzero rate of correlated dephasing, wherein the signal includes information about a matrix, the matrix including diagonal elements and off-diagonal elements, and wherein the off-diagonal elements of the matrix are 2s-sparse;
performing randomized measurements of the off-diagonal elements of the matrix by preparing entangled Greenberger-Horne-Zeilinger states (GHZ states) on random subsets of the plurality of qubits;
recovering the matrix based on a direct measurement of the diagonal elements of the matrix; and
estimating a two-qubit correlated dephasing error based on the recovered matrix.