Method and device for determining fidelity of quantum bit read signal

Abstract

The invention belongs to the technical field of quantum measurement and control, and particularly relates to a method and device for determining fidelity of a quantum bit reading signal, and the method comprises the steps: obtaining measurement data corresponding to the reading signal when a quantum bit is in two known and different quantum states, wherein the measurement data is scatter data of an IQ coordinate system; processing all the measurement data based on a two-dimensional Gaussian mixture model to obtain respective parameter values of the two two-dimensional Gaussian mixture models contained in the two-dimensional Gaussian mixture model; determining a determination Gaussian model corresponding to each quantum state according to the parameter value and the spatial distribution characteristics of the measurement data in the IQ coordinate system; and determining the fidelity of the corresponding quantum bit reading signal according to the degree that the measurement data of thequantum state meets the corresponding determined Gaussian model. According to the method, the accuracy of determining the fidelity of the quantum bit reading signal can be improved, and more accuratereference is provided for quantum measurement and control and quantum calculation.

Description

technical field [0001] The invention belongs to the technical field of quantum measurement and control, in particular to a method and a device for determining the fidelity of qubit read signals. Background technique [0002] Qubit is the carrier of information processing in quantum computing. It can be realized by any two-level system that satisfies the physical laws of quantum mechanics. Common physical systems include superconducting Joseph junctions, semiconductor quantum dots, and ion traps. The qubit has two states with different energies: |0> state and |1> state, which can be in any superposition state of |0> state and |1> state, so the accurate measurement of the qubit state is to realize the quantum prerequisites for the calculation. [0003] For the qubit represented by the two-level model, such as the qubit realized by the superconducting Josephson junction, in the measurement process, multiple experiments are required to prepare the specified quantum ...

AI Technical Summary

Problems solved by technology

However, in the process of data processing, the real distribution of the measurement data of two known and different quantum states is often not fully considered, resulting in inaccurate processing results, which in turn affects the accurate acquisition of fidelity and reduces fidelity. The degree provides reference for quantum measurement and control and quantum computing

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