Partial structural restoring of two-qubit transferred state

TL;DR

This paper presents a method to restore the non-diagonal part of a two-qubit quantum state at a remote receiver using an extended receiver and unitary transformations, demonstrated on a 42-spin system.

Contribution

It introduces a technique for partial structural restoration of two-qubit states in quantum communication lines using optimized unitary transformations.

Findings

Successful restoration of the non-diagonal state structure at the receiver.

Analysis of obstacles in restoring the diagonal part of the state.

Implementation demonstrated on a 42-spin quantum system.

Abstract

We consider the communication line with two-qubit sender and receiver, the later is embedded into the four-qubit extended receiver. Using the optimizing unitary transformation on the extended receiver we restore the structure of the non-diagonal part of an arbitrary initial sender's state at the remote receiver at certain time instant. Obstacles for restoring the diagonal part are discussed. We represent examples of such structural restoring in a communication line of 42 spin-1/2 particles.