  Quantum heat machines, encompassing heat engines, refrigerators, heaters, and
accelerators, represent the forefront of quantum thermodynamics, offering a
novel paradigm for converting heat energy into useful mechanical work.
Leveraging quantum mechanical principles, these machines promise superior
efficiency and performance compared to classical counterparts, with potential
applications in renewable energy and quantum computing. This paper investigates
a quantum Otto engine operating in both ideal and finite-time scenarios,
employing a two-level system interacting with a harmonic oscillator within the
framework of the anisotropic quantum Rabi-Stark model (AQRSM) as the working
medium. This model is notable for exhibiting both first-order and continuous
quantum phase transitions. By focusing on quantum heat engines, our study
reveals that these phase transitions critically modulate the efficiency and
power of AQRSM-based engines, outperforming quantum engines fueled by working
medium with harmonic spectrum. Additionally, we explore the impacts of quantum
friction and conduct limit cycle analysis in finite-time operations, providing
insights into optimizing quantum heat engines for practical implementation.
