Effective Mass

EffectiveMass
   Enabled Yes/No
   KPointCoord float_list
   NumAbove integer
   NumBelow integer
   StepSize float
End
EffectiveMass
Type

Block

Description

In a semi-conductor, the mobility of electrons and holes is related to the curvature of the bands at the top of the valence band and the bottom of the conduction band. With the effective mass option, this curvature is obtained by numerical differentiation. The estimation is done with the specified step size, and twice the specified step size, and both results are printed to give a hint on the accuracy. The easiest way to use this key is to enabled it without specifying any extra options.

Enabled
Type

Bool

Default value

No

GUI name

Effective mass

Description

Compute the EffectiveMass.

KPointCoord
Type

Float List

Unit

1/Bohr

Recurring

True

GUI name

At K-point

Description

Coordinate of the k-points for which you would like to compute the effective mass.

NumAbove
Type

Integer

Default value

1

GUI name

Include N bands above

Description

Number of bands to take into account above the Fermi level.

NumBelow
Type

Integer

Default value

1

GUI name

Include N bands below

Description

Number of bands to take into account below the Fermi level.

StepSize
Type

Float

Default value

0.001

Description

Size of the step taken in reciprocal space to perform the numerical differentiation