Characterization of a Two-Photon Quantum Battery: Initial Conditions, Stability and Work Extraction

Area of Science:

• Quantum physics
• Quantum optics
• Quantum information science

Background:

• Quantum batteries offer a novel approach to energy storage.
• Two-level systems coupled with cavity radiation are fundamental in quantum optics.
• Initial states of the cavity significantly influence quantum system dynamics.

Purpose of the Study:

• To analyze the performance of a quantum battery based on a two-level system and cavity radiation.
• To compare the effects of different initial cavity states (Fock, coherent, squeezed) on battery metrics.
• To evaluate key performance indicators including stored energy, charging power, and extractable work.

Main Methods:

• Modeling a quantum battery with a two-level system interacting via two-photon processes with cavity radiation.
• Investigating Fock, coherent, and squeezed states as initial conditions for the cavity.
• Analyzing figures of merit: stored energy, average charging power, energy fluctuations, and extractable work.

Main Results:

• The Fock state demonstrates superior performance for the quantum battery.
• Coherent states, despite higher energy fluctuations, show promising performance, especially for extractable work at short times.
• Performance is sensitive to the choice of initial cavity state.

Conclusions:

• The choice of initial cavity state is crucial for optimizing quantum battery performance.
• Fock states are optimal for overall battery efficiency.
• Coherent states offer a trade-off, enabling efficient work extraction under specific conditions.