(19)
(11) EP 4 227 863 A8

(12) CORRECTED EUROPEAN PATENT APPLICATION
Note: Bibliography reflects the latest situation

(15) Correction information:
Corrected version no 1 (W1 A1)

(48) Corrigendum issued on:
18.10.2023 Bulletin 2023/42

(43) Date of publication:
16.08.2023 Bulletin 2023/33

(21) Application number: 22156614.4

(22) Date of filing: 14.02.2022
(51) International Patent Classification (IPC): 
G06N 10/70(2022.01)
(52) Cooperative Patent Classification (CPC):
G06N 10/70
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
KH MA MD TN

(71) Applicant: Instytut Informatyki Teoretycznej i Stosowanej PAN
44-100 Gliwice (PL)

(72) Inventors:
  • KUKULSKI, Ryszard
    44-100 Gliwice (PL)
  • PAWELA, Lukasz
    44-100 Gliwice (PL)
  • PUCHALA, Zbigniew
    44-100 Gliwice (PL)

(74) Representative: Markieta, Jaroslaw Franciszek 
Kancelaria Rzeczników Patentowych J. Markieta, M. Zielinska-Lazarowicz Sp. p. Bukowinska 2 lok 160
02-703 Warszawa
02-703 Warszawa (PL)

   


(54) A QUANTUM PROBABILISTIC ERROR CORRECTION METHOD


(57) A quantum computer implemented probabilistic error correction method for use with quantum circuits with a noise channel N(X) that has a Choi rank not greater than two, such as N(X) = N0XN0 + N1XN1. The method comprising steps of: encoding a first qubit into an encoded state |ψ〉, putting a second qubit into an arbitrary fixed state |d1〉, implementing two qubit unitary operation UE on the first qubit and the second qubit to obtain an encoded state UE(||ψ〉 ⊗ |d1〉), and after the encoded state is affected by the noise N(X), implementing two qubit unitary operation UD, followed by measuring the second qubit in the {|d2〉,

} basis measurement to obtain a classical label i ∈ {0,1}, next preparing a third qubit in the arbitrary fixed state |d3〉, and implementing two qubit unitary operation VD on the first qubit and the third qubit, followed by measuring the third qubit in the {|d4〉,

} basis measurement to obtain a classical label j ∈ {0,1}, and when (i,j) = (0,0) accepting as an output δexp a decoded state of the first qubit, and when (i,j) ≠ (0,0) rejecting the output δexp of a decoded state of the first qubit.