An Entanglement Enrichment Method Based on Parity Check Gate Logic w

Abstract

An entanglement enrichment method based on a logic W of a parity check gate, including the following steps, step S1, constructing a W state with the GHZ state as a logic bit, and then performing entanglement distribution, and distributing the logic bits to Alice, Bob and Chalice; Step S2, any two of the three parties construct an auxiliary photon after receiving the distributed logical bits, and then input the auxiliary photon and the logical bits distributed by themselves into the parity check gate, and then check the coherent state in the parity check gate Perform homodyne measurement to obtain the phase offset of the coherent state, and select the entangled state according to the phase offset; in step S3, if the entangled state of the two parties is selected correctly, the maximum entangled state can be obtained, and the entanglement is successful. If the state selection is wrong, step S2 is performed again. In this method, the parity check gate is firstly designed according to the characteristics of the logical W state, and then the logical W state is condensed by using the parity check gate. Since the parity check gate can perform non-destructive measurement, new entanglement can be performed on the basis of the failure of entanglement concentration. Concentration to improve resource utilization.

Description

technical field [0001] The invention belongs to the technical field of quantum communication, and in particular relates to an entanglement concentration method based on logic W of a parity check gate. Background technique [0002] Quantum entanglement is a very important resource in the fields of quantum computing and quantum communication. Usually an important step before doing computation and communication is maximum entanglement distribution. Due to the interference of the external environment, problems such as photon loss and decoherence will appear in the process of entanglement distribution. The loss of photons can be solved by information redundancy, that is, by encoding one physical bit of information onto multiple physical bits. We usually call multiple physical bits carrying one bit of information logical bits; and decoherence can be used Entanglement concentration is used to solve the problem, so that the non-maximally entangled state after decoherence is transf...

AI Technical Summary

Problems solved by technology

Due to the interference of the external environment, problems such as photon loss and decoherence will occur in the process of entanglement distribution.

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