Single-shot error mitigation by coherent Pauli checks

Generating samples from the output distribution of a quantum circuit is a ubiquitous task used as a building block of many quantum algorithms. Here we show how to accomplish this task on a noisy quantum processor lacking full-blown error correction for a special class of quantum circuits dominated b...

Full description

Bibliographic Details
Main Authors: Ewout van den Berg, Sergey Bravyi, Jay M. Gambetta, Petar Jurcevic, Dmitri Maslov, Kristan Temme
Format: Article
Language:English
Published: American Physical Society 2023-09-01
Series:Physical Review Research
Online Access:http://doi.org/10.1103/PhysRevResearch.5.033193
_version_ 1797210382401536000
author Ewout van den Berg
Sergey Bravyi
Jay M. Gambetta
Petar Jurcevic
Dmitri Maslov
Kristan Temme
author_facet Ewout van den Berg
Sergey Bravyi
Jay M. Gambetta
Petar Jurcevic
Dmitri Maslov
Kristan Temme
author_sort Ewout van den Berg
collection DOAJ
description Generating samples from the output distribution of a quantum circuit is a ubiquitous task used as a building block of many quantum algorithms. Here we show how to accomplish this task on a noisy quantum processor lacking full-blown error correction for a special class of quantum circuits dominated by Clifford gates. Our approach is based on coherent Pauli checks (CPCs) that detect errors in a Clifford circuit by verifying commutation rules between random Pauli-type check operators and the considered circuit. Our main contributions are as follows. First, we derive a simple formula for the probability that a Clifford circuit protected by CPCs contains a logical error. In the limit of a large number of checks, the logical error probability is shown to approach the value ≈7εn/5, where n is the number of qubits and ε is the depolarizing error rate. Our formula agrees nearly perfectly with the numerical simulation results. Second, we show that CPCs are well suited for quantum processors with a limited qubit connectivity. For example, the difference between all-to-all and linear qubit connectivity is only a 3× increase in the number of cnot gates required to implement CPCs. Third, we describe simplified one-sided CPCs, which are well suited for mitigating measurement errors in the single-shot settings. Finally, we report an experimental demonstration of CPCs with up to 10 logical qubits and more than 100 logical cnot gates. Our experimental results show that CPCs provide a marked improvement in the logical error probability for the considered task of sampling the output distribution of quantum circuits.
first_indexed 2024-04-24T10:09:42Z
format Article
id doaj.art-8485be8fe5e44aac8507d96c2c968734
institution Directory Open Access Journal
issn 2643-1564
language English
last_indexed 2024-04-24T10:09:42Z
publishDate 2023-09-01
publisher American Physical Society
record_format Article
series Physical Review Research
spelling doaj.art-8485be8fe5e44aac8507d96c2c9687342024-04-12T17:34:11ZengAmerican Physical SocietyPhysical Review Research2643-15642023-09-015303319310.1103/PhysRevResearch.5.033193Single-shot error mitigation by coherent Pauli checksEwout van den BergSergey BravyiJay M. GambettaPetar JurcevicDmitri MaslovKristan TemmeGenerating samples from the output distribution of a quantum circuit is a ubiquitous task used as a building block of many quantum algorithms. Here we show how to accomplish this task on a noisy quantum processor lacking full-blown error correction for a special class of quantum circuits dominated by Clifford gates. Our approach is based on coherent Pauli checks (CPCs) that detect errors in a Clifford circuit by verifying commutation rules between random Pauli-type check operators and the considered circuit. Our main contributions are as follows. First, we derive a simple formula for the probability that a Clifford circuit protected by CPCs contains a logical error. In the limit of a large number of checks, the logical error probability is shown to approach the value ≈7εn/5, where n is the number of qubits and ε is the depolarizing error rate. Our formula agrees nearly perfectly with the numerical simulation results. Second, we show that CPCs are well suited for quantum processors with a limited qubit connectivity. For example, the difference between all-to-all and linear qubit connectivity is only a 3× increase in the number of cnot gates required to implement CPCs. Third, we describe simplified one-sided CPCs, which are well suited for mitigating measurement errors in the single-shot settings. Finally, we report an experimental demonstration of CPCs with up to 10 logical qubits and more than 100 logical cnot gates. Our experimental results show that CPCs provide a marked improvement in the logical error probability for the considered task of sampling the output distribution of quantum circuits.http://doi.org/10.1103/PhysRevResearch.5.033193
spellingShingle Ewout van den Berg
Sergey Bravyi
Jay M. Gambetta
Petar Jurcevic
Dmitri Maslov
Kristan Temme
Single-shot error mitigation by coherent Pauli checks
Physical Review Research
title Single-shot error mitigation by coherent Pauli checks
title_full Single-shot error mitigation by coherent Pauli checks
title_fullStr Single-shot error mitigation by coherent Pauli checks
title_full_unstemmed Single-shot error mitigation by coherent Pauli checks
title_short Single-shot error mitigation by coherent Pauli checks
title_sort single shot error mitigation by coherent pauli checks
url http://doi.org/10.1103/PhysRevResearch.5.033193
work_keys_str_mv AT ewoutvandenberg singleshoterrormitigationbycoherentpaulichecks
AT sergeybravyi singleshoterrormitigationbycoherentpaulichecks
AT jaymgambetta singleshoterrormitigationbycoherentpaulichecks
AT petarjurcevic singleshoterrormitigationbycoherentpaulichecks
AT dmitrimaslov singleshoterrormitigationbycoherentpaulichecks
AT kristantemme singleshoterrormitigationbycoherentpaulichecks