88 lines
2.7 KiB
Fortran
88 lines
2.7 KiB
Fortran
|
!
|
||
|
|
!=======================================================================
|
||
|
|
!
|
||
|
|
MODULE UTIC_PARAMETERS
|
||
|
|
!
|
||
|
|
USE ACCURACY_REAL
|
||
|
|
!
|
||
|
|
CONTAINS
|
||
|
|
!
|
||
|
|
!
|
||
|
|
!=======================================================================
|
||
|
|
!
|
||
|
|
SUBROUTINE UTIC_PARAM(X,RS,T,OMQ,OM0)
|
||
|
|
!
|
||
|
|
! This subroutine computes the OMEGA(q) and OMEGA(0) parameters
|
||
|
|
! entering the Utsumi-Ichimaru dielectric function approach
|
||
|
|
!
|
||
|
|
! Reference: (1) K. Utsumi and S. Ichimaru,
|
||
|
|
! Phys. Rev. B 22, 1522-1533 (1980)
|
||
|
|
!
|
||
|
|
!
|
||
|
|
! Input parameters:
|
||
|
|
!
|
||
|
|
! * X : dimensionless factor --> X = q / (2 * k_F)
|
||
|
|
! * RS : Wigner-Seitz radius (in units of a_0)
|
||
|
|
! * T : temperature (in SI)
|
||
|
|
!
|
||
|
|
!
|
||
|
|
! Intermediate parameters:
|
||
|
|
!
|
||
|
|
! * SQ_TYPE : structure factor approximation (3D)
|
||
|
|
! * GQ_TYPE : local-field correction type (3D)
|
||
|
|
! * EC_TYPE : type of correlation energy functional
|
||
|
|
! * IQ_TYPE : type of approximation for I(q)
|
||
|
|
!
|
||
|
|
! Output parameters:
|
||
|
|
!
|
||
|
|
! * OMQ : OMEGA(q) characteristic frequency
|
||
|
|
! * OM0 : OMEGA(0) parameter = lim_{q --> 0} OMEGA(q)
|
||
|
|
!
|
||
|
|
! Author : D. Sébilleau
|
||
|
|
!
|
||
|
|
! Last modified : 3 Dec 2020
|
||
|
|
!
|
||
|
|
!
|
||
|
|
USE REAL_NUMBERS, ONLY : ZERO,ONE,TWO,HALF
|
||
|
|
USE CONSTANTS_P1, ONLY : H_BAR
|
||
|
|
USE FERMI_SI, ONLY : EF_SI,KF_SI
|
||
|
|
USE PI_ETC, ONLY : PI,PI_INV
|
||
|
|
USE LF_VALUES, ONLY : GQ_TYPE,IQ_TYPE
|
||
|
|
USE SF_VALUES, ONLY : SQ_TYPE
|
||
|
|
USE ASYMPT, ONLY : G0,GI
|
||
|
|
USE RELAXATION_TIME_STATIC, ONLY : UTIC_RT_3D
|
||
|
|
USE IQ_FUNCTIONS_1
|
||
|
|
USE LOCAL_FIELD_STATIC
|
||
|
|
USE PLASMON_ENE_SI
|
||
|
|
!
|
||
|
|
IMPLICIT NONE
|
||
|
|
!
|
||
|
|
REAL (WP), INTENT(IN) :: X,RS,T
|
||
|
|
REAL (WP), INTENT(OUT) :: OMQ,OM0
|
||
|
|
REAL (WP) :: Y,OMP
|
||
|
|
REAL (WP) :: IQ,GQ,TAU_Q
|
||
|
|
REAL (WP) :: COEF
|
||
|
|
!
|
||
|
|
REAL (WP) :: SQRT
|
||
|
|
!
|
||
|
|
Y = X + X ! q / k_F
|
||
|
|
OMP = ENE_P_SI / H_BAR ! omega_p in SI
|
||
|
|
!
|
||
|
|
! Computing the static values I(q) and G(q)
|
||
|
|
!
|
||
|
|
CALL IQ_3D(X,RS,IQ_TYPE,IQ) !
|
||
|
|
CALL LOCAL_FIELD_STATIC_3D(X,RS,T,GQ_TYPE,GQ) !
|
||
|
|
!
|
||
|
|
! Computing the relaxation time TAU_Q
|
||
|
|
!
|
||
|
|
TAU_Q = UTIC_RT_3D(X,RS,T,SQ_TYPE,GQ_TYPE) !
|
||
|
|
!
|
||
|
|
COEF = SQRT(HALF * PI) * OMP * OMP * TAU_Q !
|
||
|
|
!
|
||
|
|
OMQ = COEF * (GQ - IQ) ! ref. 1 eq. (3.19)
|
||
|
|
OM0 = COEF * Y * Y * (G0 - GI) ! ref. 1 eq. (5.7)
|
||
|
|
!
|
||
|
|
END SUBROUTINE UTIC_PARAM
|
||
|
|
!
|
||
|
|
END MODULE UTIC_PARAMETERS
|