MSc. Thesis Defense: Beyza Aslanbaş

Effects of Quantum Confinement and Coherence in Finite-Time Quantum Szilard Engine

Beyza Aslanbaş
Physics, MSc. Thesis, 2025

Thesis Jury

Asst. Prof. Dr Alhun Aydın (Thesis Advisor)

Prof. Dr. Zafer Gedik

Prof. Dr. Özgür E. Müstecaplıoğlu.

Date & Time: July 18th, 2025 – 3.40 PM

Place: FENS L063

Keywords: finite-time heat engine, Landauer Principle, information

thermodynamics, open quantum systems

Abstract

The Szilard engine is a foundational thought experiment that rigorously links thermodynamics and information theory. With the miniaturization of devices and ongoing progress in quantum information science, it is crucial to examine how quantum effects influence the operation of such engines. This thesis investigates the finite-time dynamics of a quantum Szilard engine subjected to size-invariant shape transformations, in which the geometry of the confinement potential is deformed without altering its overall size. The system’s evolution is modeled using a time-dependent, Markovian LGKS (Lindblad-Gorini-Kossakowski-Sudarshan) master equation. We numerically solve this equation to analyze the thermodynamic behavior of the engine, focusing on the roles of quantum coherence and its interplay with heat, work, and entropy throughout the cycle. Special attention is given to how coherence evolves under varying barrier insertion rates and thermalization temperatures. We demonstrate that coherence generation is strongly influenced by both the protocol speed and the bath temperature. Furthermore, we show a connection between coherence accumulation and the energetic and informational cost of the cycle. These findings enhance our understanding of coherence in finite-time, measurement-based quantum devices and suggest that geometric deformations can serve as a powerful tool for thermodynamic control in quantum technologies.