State preparation in a Jaynes-Cummings lattice with quantum optimal control

Area of Science:

• Quantum physics
• Many-body systems
• Quantum information science

Background:

• Preparing high-fidelity quantum states in interacting many-body systems is challenging due to unknown states and decoherence.
• Existing methods like adiabatic approaches have limitations in speed and fidelity.

Purpose of the Study:

• To investigate a quantum optimal control (QOC) approach for rapid and high-fidelity ground state preparation.
• To analyze the performance of QOC in a finite-sized Jaynes-Cummings lattice with unit filling.
• To explore the relationship between QOC performance, evolution time, parameter constraints, and the quantum speed limit.

Main Methods:

• Utilizing a quantum optimal control (QOC) framework.
• Simulating a finite-sized Jaynes-Cummings lattice model at unit filling.
• Analyzing the fidelity of generated quantum states as a function of evolution time and control parameters.

Main Results:

• QOC achieves high-fidelity quantum many-body state preparation when evolution time exceeds a specific threshold.
• The QOC approach demonstrates superior performance compared to the adiabatic approach.
• The threshold time is dependent on parameter constraints and linked to the quantum speed limit.
• The QOC method exhibits robustness against control errors.

Conclusions:

• Quantum optimal control offers a powerful and efficient method for preparing quantum ground states in complex many-body systems.
• QOC provides a viable alternative to adiabatic methods, overcoming limitations in speed and fidelity.
• The findings suggest potential for significant advancements in applying QOC to practical quantum state preparation challenges.