Temperature-dependent remote control of polarization and coherence intensity with pure sender's initial state

TL;DR

This paper investigates how temperature influences the remote creation of polarization and coherence intensity in long spin-1/2 chains, revealing how initial states and chain length affect these quantum properties.

Contribution

It introduces a model for remote state creation using pure sender states and thermal equilibrium nodes, analyzing the effects of temperature and chain length on polarization and coherence.

Findings

Coherence intensity requires large polarization in long chains.

Coherence intensity diminishes as chain length increases.

Polarization remains relatively unaffected by chain length.

Abstract

We study the remote creation of the polarization and intensity of the first-order coherence (or coherence intensity) in long spin-1/2 chains with one qubit sender and receiver. Therewith we use a physically motivated initial condition with the pure state of the sender and the thermodynamical equilibrium state of the other nodes. The main part of the creatable region is a one-to-one map of the initial-state (control) parameters, except the small subregion twice covered by the control parameters, which appears owing to the chosen initial state. The polarization and coherence intensity behave differently in the state creation process. In particular, the coherence intensity can not reach any significant value unless the polarization is large in long chains (unlike the short ones), but the opposite is not true. The coherence intensity vanishes with an increase in the chain length, while the polarization (by absolute value) is not sensitive to this parameter. We represent several characteristics of the creatable polarization and coherence intensity and describe their relation to the parameters of the initial state. The link to the eigenvalue-eigenvector parametrization of the receiver's state-space is given.