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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators

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Deriving the Landauer Principle From the Quantum Shannon Entropy.

Henrik J Heelweg¹, Amro Dodin², Adam P Willard¹

¹Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.

The Journal of Physical Chemistry Letters

|January 30, 2025

Summary

This summary is machine-generated.

We derived a formula for quantum probability distributions in noisy environments. This reveals that resetting quantum bits (qubits) costs more free energy than in classical systems, depending on environment and state fidelity.

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Area of Science:

Quantum thermodynamics
Statistical mechanics
Quantum information theory

Background:

Understanding quantum states in thermal environments is crucial for quantum technologies.
Classical thermodynamics provides a framework for energy costs but doesn't fully capture quantum effects.

Purpose of the Study:

To derive an expression for the equilibrium probability distribution of a quantum state interacting with a noisy thermal environment.
To establish a statistical mechanical interpretation for calculating minimum free energy costs of quantum state changes.
To investigate the factors influencing the free energy cost of erasing or resetting a qubit.

Main Methods:

Derivation of probability distribution separating quantum and classical uncertainty.
Application of statistical mechanics to determine free energy costs.
Analysis of system-bath entanglement effects on energy costs.

Main Results:

An expression for the equilibrium probability distribution of a quantum state in a noisy thermal environment was derived.
Minimum free energy costs for quantum state changes were determined using a statistical mechanical interpretation.
The free energy cost to reset a qubit was found to depend on target state fidelity and environmental properties, unlike classical systems.

Conclusions:

Quantum and classical uncertainties can be formally separated in noisy environments.
System-bath entanglement significantly impacts the free energy costs of quantum operations.
Resetting qubits requires careful consideration of environmental factors and state fidelity, highlighting differences from classical systems.