High order Chin actions in path integral Monte Carlo

Area of Science:

• Computational Physics
• Quantum Many-Body Systems

Background:

• Path integral Monte Carlo (PIMC) simulations are crucial for studying quantum systems.
• Existing actions, like the Takahashi-Imada action, have limitations in accuracy and error control.

Purpose of the Study:

• To implement and evaluate the Chin action in PIMC simulations for the first time.
• To assess the accuracy and efficiency improvements offered by the Chin action compared to standard methods.

Main Methods:

• The Chin action, a fully fourth-order accurate formulation, was incorporated into PIMC simulations.
• Two free parameters within the Chin action were optimized to minimize time step errors.
• The performance was tested on a one-dimensional harmonic oscillator, H(2) droplet, and bulk liquid 4He.

Main Results:

• The optimized Chin action exhibited a sixth-order dependence on the time step error.
• A significant efficiency improvement of approximately a factor of 10 was achieved over the primitive approximation.
• The number of beads required was substantially reduced, comparable to the pair action approximation for superfluid 4He.

Conclusions:

• The Chin action provides a highly accurate and tunable approach for PIMC simulations.
• This method offers substantial computational savings and improved efficiency for quantum many-body problems.
• The findings demonstrate the broad applicability of the Chin action across various quantum systems.