DSQSS is an application program for solving quantum many body problems in a discrete set (typically a lattice). It carries out quantum Monte Carlo simulations that sample from the Feynman path integral using the worm update. It can handle any lattice geometry and interaction.

## Homepage

• dsqss-2.0.4 (2023/02/01)

## How to use DSQSS on the ISSP supercomputer

• DSQSS is installed in /home/issp/materiapps/intel/dsqss/
• Execution files of DSQSS are available in /home/issp/materiapps/intel/dsqss/dsqss-VERSION/bin
• Document  of DSQSS is available in /home/issp/materiapps/intel/dsqss/dsqss-VERSION/doc
• Sample files of DSQSS are available in /home/issp/materiapps/intel/dsqss/dsqss-VERSION/share/dsqss/VERSION/samples

#### How to run DSQSS

As a simple example, we will now calculate the antiferromagnetic Heisenberg dimer.

1. Set up paths and modules in advance
$source /home/issp/materiapps/intel/dsqss/dsqssvars.sh  2. Prepare the input file std.toml (# and below are comments). You will find the same in the sample directory, dla/01_spindimer. [hamiltonian] model = "spin" M = 1 # S=1/2 Jz = -1.0 # coupling constant, negative for AF Jxy = -1.0 # coupling constant, negative for AF h = 0.0 # magnetic field [lattice] lattice = "hypercubic" # hypercubic, periodic dim = 1 # dimension L = 2 # number of sites along each direction bc = false # open boundary [parameter] beta = 100 # inverse temperature nset = 5 # set of Monte Carlo sweeps npre = 10 # MCSteps to estimate hyperparameter ntherm = 10 # MCSweeps for thermalization nmcs = 100 # MCSweeps for measurement seed = 31415 # seed of RNG 3. Execute the input file conversion script dla_pre.py with std.toml. $ dla_pre std.toml
4. Copy the sample script and run the calculation.
$cp /home/issp/materiapps/intel/dsqss/sample_jobscript/dsqss.sh .$ sbatch dsqss.sh
5. The calculation results are written to sample.log.
\$ grep ene sample.log
R ene = -3.76420000e-01 1.54950926e-03

ene is energy per site.

## Measurement of the number of times used

• We measure the number of uses of PASUMS software on the ISSP supercomputer. This becomes an important indicator for evaluating the significance of the project, and we appreciate your cooperation. We can also count the number of users who use versions of the software that are not pre-installed, so we would appreciate your cooperation in counting the number of users to help us understand how the software is being used (for details, please click here). If you do not wish to measure utilization when using pre-installed software, please select dla_nocount/pmwa_B_nocount/pmwa_H_nocount as the executable file.

## Contact

• How to use DSQSS (e.g., create inputs), functions, etc.
• How to Execute on ISSP Supercomputer System
• Software Consultation Service for ISSP Supercomputer
center-apps__at__issp.u-tokyo.ac.jp (please replace __at__ by @)