Thermodynamic Performance of a Measurement-Driven Quantum Engine with a Two-Parameter
(p,q)-Deformed Harmonic Oscillator
We address a measurement-driven, single-bath quantum engine that generates usable work using quantum measurement backaction. The working medium is a two-parameter
(p,q)-deformed harmonic oscillator, whose nonlinear spectrum modifies the energy gaps sampled by a nonselective Gaussian measurement and the work exchanged during quasistatic adiabatic strokes. The cycle starts from a Gibbs state and consists of an adiabatic change of
(ω,p,q), measurement of the final effective position quadrature, a reverse adiabatic stroke, and thermalization with the original bath. Using a consistent first-law convention, we derive the measurement heat, adiabatic work contributions, thermalization heat, and reduced working-medium efficiency. We also express the measurement stroke via a transition matrix and identify passivity/unitality conditions that ensure nonnegative measurement heat. Numerical scans show that, within the finite-basis, spectral-ordering, and engine-operation checks used in this work, deformation can enhance measurement-induced energy input and extracted work relative to the undeformed oscillator. The physical engine regime is selected by $\QM>0$, $\Wcyc<0$, $\QT<0$, and
0<η<1. The reported efficiency is reduced and excludes measurement-apparatus costs.
This paper gives an introduction on the basic concepts of quantum heat engine and quantum thermodynamics while exploring relevant properties of the quantum heat engine system based on coupled harmonic oscillators. The authors drew references from classical thermodynamics and introduces Bogoliubov transformation so as to diagonalize the potential term in coupled quantum harmonic oscillators. The authors also based the quantum heat engine system on said oscillators and gives a detailed demonstration of acquiring the efficiency of Otto cycle utilized by this system, arriving at the conclusion that there is a unifying and cohesive factor that interconnects certain corresponding values between classical and quantum heat engines.
In this work we present the concept of a quantum flywheel coupled to a quantum heat engine. The flywheel stores useful work in its energy levels, while additional power is extracted continuously from the device. Generally, the energy exchange between a quantum engine and a quantized work repository is accompanied by heat, which degrades the charging efficiency. Specifically when the quantum harmonic oscillator acts as a work repository, quantum and thermal fluctuations dominate the dynamics. Quantum monitoring and feedback control are applied to the flywheel in order to reach steady state and regulate its operation. To maximize the charging efficiency one needs a balance between the information gained by measuring the system and the information fed back to the system. The dynamics of the flywheel are described by a stochastic master equation that accounts for the engine, the external driving, the measurement, and the feedback operations.