Parameter: mstep

Definition

We can use the delayed Green's function updating algorithm^[1] to accelerate the Hirsch-Fye quantum Monte Carlo impurity solver (the DAISY component in the iQIST software package). Here, the mstep parameter denotes the maximum number of delayed update steps which is the key control parameter for this algorithm.

Type

Integer

Default value

16

Component

Only for the DAISY component.

Behavior

There are two possible choices for mstep parameter so far:

• mstep = 1, using traditional update algorithm, low efficiency.

• mstep > 1, using delayed update algorithm to improve the computational efficiency.

Comment

mstep = 16 is an optimal choice. Do not change it rashly.

Reference