Entropy Distribution in a Quantum Informational Circuit of Tunable Szilard Engines

Jose Diazdelacruz

doi:10.3390/e21100980

Abstract

This paper explores the possibility of extending the existing model of a single-particle Quantum Szilard Engine to take advantage of some features of quantum information for driving typical mechanical systems. It focuses on devices that output mechanical work, extracting energy from a single thermal reservoir at the cost of increasing the entropy of a qubit; the reverse process is also considered. In this alternative, several engines may share the information carried by the same qubit, although its interception will prove completely worthless for any illegitimate user. To this end, multi-partite quantum entanglement is employed. Besides, some changes in the cycle of the standard single-particle Quantum Szilard Engine are described, which lend more flexibility to meeting additional requirements in typical mechanical systems. The modifications allow having qubit input and output states of adjustable entropy. This feature enables the possibility of chaining the qubit between engines so that its output state from one can be used as an input state for another. Finally, another tweak is presented that allows for tuning the average output force of the engine.

Highlights

The capacity of performing mechanical, electrical, or any other kind of work is a valuable resource that is ruled by the laws of Thermodynamics
We describe a system that enables the use of a qubit as a resource for several information heat engines in a row, keeping it protected in its journey from one to the
As a result of the considerations set forth in the previous section, we claim that it is possible to devise a mechanical system of cylinders that share effective mechanical power through a common informational line, provided that they have access to a thermal reservoir

Summary

Introduction

The capacity of performing mechanical, electrical, or any other kind of work is a valuable resource that is ruled by the laws of Thermodynamics. Bits or qubits in a non-maximum entropy state are valuable resources that should be kept hidden from illegitimate users Under this denomination, we include any unwanted owner of an information heat engine that could intercept a qubit and obtain work in exchange for an entropy increase. This work describes some slight changes that allow to input non-minimum and output non-maximum entropy bits in a way that allows them to be used by several devices consecutively With this tweak, there is a parallel between hydraulic cylinders and Szilard Engines. Two versions of it are presented: one for producing work (motor mode) and another for decreasing the entropy of the circulating qubits (generator mode). The initial entropy of the target qubit conditions the fidelity of the measurement and the result of the whole process

Antecedents

Reference Quantum Szilard Engine

Protected Information Transmission with GHZ States

Partial Information Cycles for Motors and Generators

Qubit Processing by A Cylinder

Work Evaluation

Force Matching Tweak

Carnot Cycles with Szilard Cylinders

10. Discussion

11. Conclusions