Parameter: nsweep

Definition

Maximum number of quantum Monte Carlo sampling steps.

Type

Integer

Default value

20000000 (for CT-HYB impurity solvers) or 240000 (for HF-QMC impurity solver)

Component

ALL

Behavior

This is the number of Monte Carlo sampling steps conducted by the current process. If you run the quantum impurity solvers parallelly with $N_{\text{procs}}$ processes, then the total number of Monte Carlo sampling steps in the calculation is

\[N_{\text{procs}} \times \text{nsweep}\]

Larger the nsweep is, more accurate and more time-consuming the calculation is. If you conduct the quantum impurity solver on many cores, you can decrease nsweep. But the minimal value of it should not be less than its default value.

Comment

In order to improve the numerical quality and suppress the numerical noise, the most direct and practicable route is to increase nsweep.

If the data binning mode is activated, nsweep should not be larger than 200000000.

nsweep should be always larger than ntherm, nwrite, nmonte, and ncarlo.

See also ntherm, nwrite, nmonte, ncarlo parameters for more details.