US 12,380,355 B2
Automatic qubit calibration
Julian Shaw Kelly, Santa Barbara, CA (US)
Assigned to Google LLC, Mountain View, CA (US)
Filed by Google LLC, Mountain View, CA (US)
Filed on Dec. 23, 2022, as Appl. No. 18/088,265.
Application 18/088,265 is a continuation of application No. 17/218,867, filed on Mar. 31, 2021, granted, now 11,567,842.
Application 17/218,867 is a continuation of application No. 16/743,874, filed on Jan. 15, 2020, granted, now 10,997,044, issued on May 4, 2021.
Application 16/743,874 is a continuation of application No. 15/948,490, filed on Apr. 9, 2018, granted, now 10,606,720, issued on Mar. 31, 2020.
Application 15/948,490 is a continuation of application No. 15/178,136, filed on Jun. 9, 2016, granted, now 9,940,212, issued on Apr. 10, 2018.
Prior Publication US 2023/0130488 A1, Apr. 27, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G06F 11/00 (2006.01); G06F 11/22 (2006.01); G06F 15/82 (2006.01); G06N 10/40 (2022.01); G06N 10/70 (2022.01)
CPC G06N 10/40 (2022.01) [G06F 11/00 (2013.01); G06F 11/2236 (2013.01); G06F 11/2247 (2013.01); G06F 11/2273 (2013.01); G06F 15/82 (2013.01); G06N 10/70 (2022.01)] 21 Claims
OG exemplary drawing
 
1. A method performed by a qubit calibration system, the method comprising:
monitoring, during a quantum computation performed by a quantum computing device that comprises multiple physical qubits, values of system parameters to identify a system parameter that is out of specification;
selecting a set of system parameters that includes the identified system parameter and system parameters that depend on the identified system parameter, wherein the set of system parameters defines a directed graph comprising a node for each system parameter in the set, the identified system parameter corresponding to a root node, and a directed edge for each dependency; and
calibrating parameters in the set of system parameters in sequence according to a node ancestry ordering for the directed graph, wherein the sequence begins with the root node, the calibrating comprising, for each parameter in the sequence:
applying a set of waveforms to a physical qubit that corresponds to the parameter and measuring the physical qubit to obtain a respective set of measured qubit states; and
updating the parameter based on the set of measured qubit states.