Verfahren und System zur Durchführung eines Gate mit Gesteuertem Z zwischen Qubits

Details

Veröffentlichungs-Nr.

EP4769238

Anmeldetag

27. Dezember 2024

Veröffentlichung

1. Juli 2026

Rechtsraum

EP

Abstract

Method of performing a CNOT gate between a control qubit having a control qubit resonance frequency and a target qubit having a target qubit resonance frequency, in which said control qubit and said target qubit are cat qubits hosted respectively in a control resonator and in a target resonator of a superconducting quantum circuit, and are stabilized therein by means of a command circuit arranged for selectively applying radiation to said superconducting quantum circuit, and in which said control resonator and said target resonator are connected via an ancilla resonator coupled to said command circuit for stabilizing a respective ancilla qubit having an ancilla qubit resonance frequency, and wherein said control qubit and said target qubit are not directly connected. Said method comprises the following operations: a) preparing (400, 700) the ancilla qubit in a state e^iϕ1Z|+〉 where ϕ 1 is a phase comprised in the range [0; π] measured around the Z axis of the ancilla qubit, b) performing a CNOT gate (410, 710) between said control qubit and said ancilla qubit, with the control qubit being the target and the ancilla qubit being the control, c1) performing a S gate (432, 732) on said target qubit, c2) performing a CNOT gate (435, 735) between said target qubit and said ancilla qubit, with the target qubit being the target and the ancilla qubit being the control, c3) performing a conjugate transpose S gate (436, 736) on said target qubit, c4) performing a S gate (438, 738) on said ancilla qubit, c5) performing a CNOT gate (439, 739) between said target qubit and said ancilla qubit, with the target qubit being the target and the ancilla qubit being the control, d) preparing (440, 740) the control qubit in a state |0) or |1〉, e) performing a CNOT gate or a zero-controlled NOT gate (450, 750) between said control qubit and said ancilla qubit, with the control qubit being the target and the ancilla qubit being the control, f) performing an MZ operation (420, 720) on said control qubit, g) deriving a quantum correction to be performed depending on the result of operation f), h) performing a measurement in the basis {e^iϕ1Z|+〉,e^iϕ1Z|-〉} (460, 760) on said ancilla qubit, i) deriving a corrective quantum Z gate to be performed depending on the result of operation h), wherein operation f) is performed after operation b) but before operation d), and wherein operation h) is performed after operations e) and c5). There is also provided a quantum system, a computer program product, and a computer-readable medium.

Anmelder

Firma

Alice & Bob

Land

🇫🇷 Frankreich