This is a quantum simulation program from the
Shumway Research Group,
which focuses on applications to nanoscience and technology.
Path integral Quantum Monte Carlo (PI-QMC) simulates particles (often electrons and ions) by
directly sampling the canonical partition function. In the path integral formulation of
quantum statistical mechanics developed by Richard Feynman, particles get represented by
closed imaginary-time trajectories of length ℏ/kT. PI-QMC simulations are able to compute
total energies, correlation functions, charge distribution, and linear response functions
for thermal equilibrium. As in many quantum Monte Carlo methods, PI-QMC has efficient scaling
with system size, often order N^{2} or N^{3}.

Our application, pi-qmc, is well-suited for modeling conduction electrons and holes in quantum dots, quantum wires, and quantum wells. For quantum dots and wires, we often generate realistic confining potentials using qdot-tools. We are also testing and developing pi-qmc for ab initio calculations, but at this point only hydrogen and helium systems work well.

To get started:

- To download the code, just download the zip file or use use git.
- This is an active research code, and currently all versions are development (beta). We highly recommend using git for easy updates.
- Read the manual: pi-qmc documentation.
- To test out pi-qmc without downloading or installing anything, try the (sadly out of date) online nanoHUB tool.

Please send me your feedback: john.shumway@asu.edu. This is my group's primary research code. Most of my efforts go towards our group research needs and collaborative science projects, but I'm making this code public to help everyone. Path integrals are fun, and I think a lot of interesting research can be enabled with some cooperation. I like to hear from other scientists, either via email or on the issues page. Instructional or tutorial material is much easier to justify if people document their interests. New developers are welcome to join this project.

This document last modified 14 December, 2013.