harmonic_bath Module Reference

Module to handle a harmonic-oscillator model for the bath in quantum dynamics simulations. More...

Functions/Subroutines
subroutine	initialize_bath
	Allocates the necessary arrays to describe the bath and system-bath interactions. Also, the spectral density is uniformly sampled according to frequency-dependent reorganization energy. More...
subroutine	sample_thermal_wigner (x_init, p_init, beta)
	Sample the initial thermal distribution for harmonic bath from the Wigner transform of the Boltzmann operator. This is under the assumption that the full initil density operator can be written as \( \hat{\rho}_s\hat{\rho}_b^{eq} \). More...
subroutine	finalize_bath
real(dp) function, dimension(nbath *nosc)	bilinear_harmonic_force_pldm (x, x_map, p_map, xt_map, pt_map)
	Calculate bilinear coupling force for PLDM. More...
real(dp) function, dimension(nbath *nosc)	bilinear_harmonic_force_twa (x, x_map, p_map)
	Calculate the bilinear coupling force for TWA and SQC calculations. More...
real(dp) function, dimension(0 :nbstep)	redfield_bath_correlation_function (sd, w, beta_local)
	Calculate the harmonic bath correlation function for a bilinearly coupled system-bath model in the Redfield Approximation for 1 ps. More...
subroutine	bath_coupled_to_vibrational_mode (q_init, pq_init, beta)
	Subroutine to prepare the spectral density that is coupled to an "intramolecular" vibrational mode. More...

Variables
real(dp), dimension(:), allocatable	x_bath
real(dp), dimension(:), allocatable	p_bath
real(dp), dimension(:), allocatable	omega
real(dp), dimension(:,:), allocatable	c
real(dp), dimension(:,:), allocatable	site_sd
real(dp), dimension(:), allocatable	site_reorg
real(dp), dimension(:), allocatable	site_bath_freq

Detailed Description

Module to handle a harmonic-oscillator model for the bath in quantum dynamics simulations.

Function/Subroutine Documentation

bath_coupled_to_vibrational_mode()

subroutine harmonic_bath::bath_coupled_to_vibrational_mode	(	real(dp), dimension(:), intent(inout)	q_init,
		real(dp), dimension(:), intent(inout)	pq_init,
		real(dp), intent(in)	beta
	)

Subroutine to prepare the spectral density that is coupled to an "intramolecular" vibrational mode.

bilinear_harmonic_force_pldm()

real(dp) function, dimension(nbath*nosc) harmonic_bath::bilinear_harmonic_force_pldm	(	real(dp), dimension(nbath*nosc), intent(in)	x,
		real(dp), dimension(nstate), intent(in)	x_map,
		real(dp), dimension(nstate), intent(in)	p_map,
		real(dp), dimension(nstate), intent(in)	xt_map,
		real(dp), dimension(nstate), intent(in)	pt_map
	)

Calculate bilinear coupling force for PLDM.

bilinear_harmonic_force_twa()

real(dp) function, dimension(nbath*nosc) harmonic_bath::bilinear_harmonic_force_twa	(	real(dp), dimension(nbath*nosc), intent(in)	x,
		real(dp), dimension(nstate), intent(in)	x_map,
		real(dp), dimension(nstate), intent(in)	p_map
	)

Calculate the bilinear coupling force for TWA and SQC calculations.

finalize_bath()

subroutine harmonic_bath::finalize_bath

(

)

initialize_bath()

subroutine harmonic_bath::initialize_bath

(

)

Allocates the necessary arrays to describe the bath and system-bath interactions. Also, the spectral density is uniformly sampled according to frequency-dependent reorganization energy.

Note: This is restricted to a single range and discretization of frequencies (defined by a single dw)

Sample bath according to the method described by Wang et al JCP 110, 4828 (1999)

Writes a log of sampled modes into a file called "sampledbath.log"

redfield_bath_correlation_function()

real(dp) function, dimension(0 : nbstep) harmonic_bath::redfield_bath_correlation_function	(	real(dp), dimension(:), intent(in)	sd,
		real(dp), dimension(:), intent(in)	w,
		real(dp), intent(in)	beta_local
	)

Calculate the harmonic bath correlation function for a bilinearly coupled system-bath model in the Redfield Approximation for 1 ps.

sample_thermal_wigner()

subroutine harmonic_bath::sample_thermal_wigner	(	real(dp), dimension(nbath*nosc), intent(out)	x_init,
		real(dp), dimension(nbath*nosc), intent(out)	p_init,
		real(dp), intent(in)	beta
	)

Sample the initial thermal distribution for harmonic bath from the Wigner transform of the Boltzmann operator. This is under the assumption that the full initil density operator can be written as \( \hat{\rho}_s\hat{\rho}_b^{eq} \).

Variable Documentation

c

real(dp), dimension(:,:), allocatable harmonic_bath::c

omega

real(dp), dimension(:), allocatable harmonic_bath::omega

p_bath

real(dp), dimension(:), allocatable harmonic_bath::p_bath

site_bath_freq

real(dp), dimension(:), allocatable harmonic_bath::site_bath_freq

site_reorg

real(dp), dimension(:), allocatable harmonic_bath::site_reorg

site_sd

real(dp), dimension(:,:), allocatable harmonic_bath::site_sd

x_bath

real(dp), dimension(:), allocatable harmonic_bath::x_bath