Thermofield theory for finite-temperature quantum chemistry

Area of Science:

• Quantum physics
• Condensed matter physics
• Physical chemistry

Background:

• Thermofield dynamics is a valuable tool in high-energy physics for handling time- and temperature-dependent phenomena.
• Its potential for investigating thermal properties of electronic systems in physics and chemistry remains largely unexplored.

Purpose of the Study:

• To establish a general framework for finite temperature correlated wave function methods.
• To introduce and evaluate two novel approaches, fixed-reference and covariant methods, for solving the imaginary time Schrödinger equation.

Main Methods:

• Development of a general framework for finite temperature correlated wave function methods.
• Implementation of fixed-reference and covariant methods based on the imaginary time Schrödinger equation.
• Application to the Hubbard model using thermal configuration interaction theory.

Main Results:

• The study demonstrates the applicability of thermofield dynamics to electronic systems.
• Comparison of fixed-reference and covariant methods applied to the Hubbard model.
• Validation of the derived methods against exact benchmark results.

Conclusions:

• Thermofield dynamics provides a robust theoretical foundation for studying thermal properties of electronic systems.
• The proposed fixed-reference and covariant methods offer effective computational strategies.
• This work bridges high-energy physics theory with condensed matter and chemical physics applications.