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nano0903c.f
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nano0903c.f
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program nano
c--- 08/05/2005/nano0805.f
c---It calculates the spin Hall effect. No disorder.
c----- 1D INFINITE WIRE
c--------Parameters:
c----CHECK FOR two terminal system , no stub, one channel N1=N2=1
IMPLICIT NONE
c=== Transmission T between different leads
Double precision Tpq,Tsum
Integer nleads,i,j,iii,jjj,Nle ! no.of leads
c=== Conductance G between different leads
Double precision Gpq,Ispins,Gspins
Double precision A1,A2,A3,C1,C2,C3
Double precision V1,V3,V4,D1,D2,D3
Double precision I1,I3,I5,I6,I2,I4,I7,I8
Double precision I1s,I2s,I3s,I4s,I5s,I6s,I7s,I8s
Double precision Etot ! total energy in range 0-0.2eV
Double precision W,Wle ! width of main wire
Double precision Mass ! GaAs mass 0.05m_0
Double precision al ! lattice constant
Double precision V! hopping parameter
DOuble precision hbar,m0 ,rashb2
Double precision Emod2,rashba,rashb,Ispin,Gspin
Double precision lstub! width of stub
Double precision pi,echarge,Emod1,Gspin1
DOUBLE PRECISION h_planck,Cp,Cpp,Wdis,dchem
Logical logus
Integer Nfin ! the no. of sites in finite part of T system
Integer N1,N2,loop1
Parameter(N1=10,N2=10,Nle=10,nleads=8)
Parameter(pi=3.14159265358979323846264d0)
Dimension Tpq(nleads,nleads),Gpq(nleads,nleads)
Dimension TSum(nleads),Gspin(10),Gspins(10)
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
common/stub/lstub,rashb,rashb2
common/dlead/Wle
common/dis/Wdis
common/dch/dchem
OPEN(UNIT=1,file='ts.dat')
OPEN(UNIT=2,file='sumy1.dat')
Open(Unit=3,file='sumy2.dat')
OPEN(UNIT=4,file='Hall.dat')
Open(Unit=7, file='tpq.dat')
logus =.false.
hbar =6.582122d-16![eV*s] Plank constant/2pi
h_planck =4.135669d-15! [eV*s]
m0 = 9.109389d-31! [kg] bare el. mass
Mass = 381d-4*m0
echarge =1.60217653d-19 ! in Coulombs
c---- I checked units twice!
c==== Number of leads
c loop1=20
W= 30d0! nm
Wle=30d0
c Mass =0.05*m0
al = Wle/(dBLE(Nle)+1d0) ! [nm]
Gspin1 =0d0
Lstub=al*(DBLE(N2)+1d0) ![nm]
Nfin =N1*N2*2 ! no. of points in x direction in finite wire!!
V=-1d0! -hbar**2/(2d0*Mass*al**2)*1d-1*1.60219d0! -1d0 [eV]
c Mass =-hbar**2*1d-1*1.60219d0/(2d0*al**2*m0*V)
iii=1
c ============
Etot =-2d0*V
rashb =2d-2
Do while ( rashb .le. -V)
c Do rashb = 1d-1,1.02d0,9d-1
rashb2=rashb*2d0*al
loop1=1
Rashba=rashb
c==== It calculates all transmission coefficients
Wdis=0d0!
c Do Wdis= 5d-2,4d0,5d-1
c DO iii=1,loop1
Call Greenji(Tpq)
Do i=1,nleads
Tsum(i) =0d0
enddo
DO i=1,nleads
Do j=1,nleads
Tsum(i)= Tsum(i)+Tpq(i,j)
enddo
write(1,*) i,Tsum(i)
enddo
Do i=1,nleads
Do j=1,nleads
Gpq(i,j) =Tpq(i,j)*echarge**2/(h_planck*echarge)
write(7,*)rashb, i,j,Tpq(i,j)
enddo
enddo
c== It calculates the conductance from transmission
c=== From the boundary conditions on currents we find voltages
c=== Current of 1 amper is going in longitudinal direction
c=== I_1+I_3 =1; -I_2-I_4=1; I_5+I_6=0
A1 =Gpq(1,2)+Gpq(1,4)+Gpq(1,5)+Gpq(1,6)+Gpq(1,7)+
& Gpq(1,8)+Gpq(3,2)+Gpq(3,4)+Gpq(3,5)+Gpq(3,7)+Gpq(3,6)
& +Gpq(3,8)
A2 = Gpq(1,6)+Gpq(1,5)+Gpq(3,5)+Gpq(3,6)
A3 = Gpq(1,8)+Gpq(1,7)+Gpq(3,7)+Gpq(3,8)
C1 =Gpq(5,3)+Gpq(5,1)+Gpq(6,1)+Gpq(6,3)
C2 = Gpq(5,3)+Gpq(5,1)+Gpq(5,2)+Gpq(5,4)+Gpq(5,7)+Gpq(5,8)
& + Gpq(6,4)+Gpq(6,2)+Gpq(6,1)+Gpq(6,3)+Gpq(6,7)+Gpq(6,8)
C3=Gpq(5,7)+Gpq(5,8)+Gpq(6,7)+Gpq(6,8)
D1 =Gpq(7,3)+Gpq(7,1)+Gpq(8,1)+Gpq(8,3)
D2 =Gpq(7,3)+Gpq(7,1)+Gpq(7,2)+Gpq(7,4)+Gpq(7,5)+Gpq(7,6)
& + Gpq(8,4)+Gpq(8,2)+Gpq(8,1)+Gpq(8,3)+Gpq(8,6)+Gpq(8,5)
D3=Gpq(7,5)+Gpq(7,6)+Gpq(8,5)+Gpq(8,6)
Cp =C1/(C2*A1-C1*A2)
Cpp =(C3*A1+C1*A3)/(C2*A1-C1*A2)
V4=(D1+D1*Cp*A2+D3*Cp*A1)/(-D1*Cpp*A2-D1*A3+D2*A1-D3*Cpp*A1)
V3 =(C1+V4*(C3*A1+C1*A3))/(C2*A1-C1*A2)! [Volt]
c==== Voltages:
V1 =(1d0+V3*A2+V4*A3)/A1 ![Volt]
I1=(Gpq(1,2)+Gpq(1,4))*V1+(Gpq(1,6)+Gpq(1,5))*(V1-V3)+
& (Gpq(1,8)+Gpq(1,7))*(V1-V4)![Ampere]
I3=(Gpq(3,4)+Gpq(3,2))*V1+
& (Gpq(3,5)+Gpq(3,6))*(V1-V3)+(Gpq(3,7)+Gpq(3,8))*(V1-V4)
I5 =Gpq(5,3)*(V3-V1)+Gpq(5,1)*(V3-V1)+Gpq(5,2)*V3+Gpq(5,4)*V3
& + Gpq(5,7)*(V3-V4)+Gpq(5,8)*(V3-V4)
I6 =Gpq(6,4)*V3+Gpq(6,2)*V3+Gpq(6,1)*(V3-V1)+Gpq(6,3)*(V3-V1)
& +Gpq(6,7)*(V3-V4)+Gpq(6,8)*(V3-V4)
I2 =(-1d0)*(Gpq(2,1)+Gpq(2,3))*V1-1d0*(Gpq(2,6)+Gpq(2,5))*V3
& -1d0*(Gpq(2,8)+Gpq(2,7))*V4
I4 =(Gpq(4,1)+Gpq(4,3))*(-V1)+(Gpq(4,6)+Gpq(4,5))*(-V3)+
& (Gpq(4,8)+Gpq(4,7))*(-V4)
I7 =Gpq(7,1)*(V4-V1)+Gpq(7,3)*(V4-V1)+(Gpq(7,2)+Gpq(7,4))*V4
& +Gpq(7,5)*(V4-V3)+Gpq(7,6)*(V4-V3)
I8 =Gpq(8,1)*(V4-V1)+Gpq(8,3)*(V4-V1)+(Gpq(8,2)+Gpq(8,4))*V4
& + (Gpq(8,5)+Gpq(8,6))*(V4-V3)
c==== I_1+I_3 =1; -I_2-I_4=1; I_5+I_6=0; I_7+I_8=0 should be fulfilled!
Ispin =hbar/(2d0*echarge)*
& (I7-I8)! spin current[eV]
c hbar/(2d0*echarge)*(I5s-I6s)
Gspin(iii) =(Ispin*1.60217653d-19/V1)/(echarge/(8d0*pi))! [e/8pi] spin Hall conductance
write(*,*) iii,Wdis,Etot,-Rashba/V,Gspin(iii)
write(2,*) Wdis,iii,Etot,-Rashba/V,Gspin(iii)
write(4,*) Wdis,Gspin(iii),I5,I6,I7,I8
logus=.false.
rashb =rashb*dsqrt(10d0)
enddo
end
c==================================================================
c----------It finds mod energy
Subroutine MODS(Emod,n,Nle)
c------- It calculates the transverse mode energy
IMPLICIT NONE
Double precision V,al,Mass,W, Etot, hbar,Emod
Double precision pi,Wle
Integer n, Nfin,Nle
Logical logus
Parameter(pi=3.14159265358979323846264d0)
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
common/dlead/Wle
Emod=2d0*V*(COS(pi*dble(n)/(dble(Nle)+1d0))-1d0)
c------- Formula for Emod was checked
return
end
c==================================================================
c--------It finds corresponding to Emod wave vector kn in lead
Subroutine Findk(Emod,kn)
c-------It finds the wave vector for traveling wave
c-------(From the condition of the total energy)
IMPLICIT NONE
Double precision Emod,Etot,V,al,Mass,W,hbar
Double Complex kn,imu
Integer Nfin
Logical logus
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
c----- Is it possible kn is complex?
c----- No, definition Tnm would be without sens.
imu =dcmplx(0d0,0d0)
kn= SQRT(2d0*Mass/(hbar**2)*(Etot-Emod)
& *10d0/1.60219d0+imu) ! I checked units twice 1/nm
return
end
c=============================================================
c==== Tight binding Hamiltonian
Subroutine Hamiltonian(Hnn)
IMPLICIT NONE
Double Complex Hnn
integer ii,Nfin,nfin1,jj
integer ihelp,infin1,infin2
integer N1, N2
double precision V,al,MAss,W ,Etot,hbar,e0,Wdis
double precision lstub,rashb,rashb2,Unitx,dchem, Rashba
double precision random
Double Complex Hx,EHx,Imunit
logical logus
Parameter(N1=10,N2=10,nfin1=N1*N2*2)
Dimension Hnn(Nfin1,Nfin1),Unitx(Nfin1,Nfin1)
Dimension Hx(Nfin1,nfin1),EHx(nfin1,nfin1)
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
common/stub/lstub,rashb,rashb2
common/dis/Wdis
common/dch/dchem
Imunit =dcmplx(0d0,1d0)
Rashba= rashb
c==== Zero starting values
Do ii=1,Nfin
Do jj=1,Nfin
Hnn(ii,jj) =dcmplx(0d0,0d0)
Unitx(ii,jj)=0d0
enddo
enddo
c=== Diagonal elements part
Do ii=1,Nfin/2
e0=random()
c e0 =Wdis*e0-Wdis/2d0
c e0=0d0 ! onsite energy
Hx(ii,ii)=Wdis*e0-Wdis/2d0-4d0*V
Hx(ii+Nfin/2,ii+Nfin/2)=Hx(ii,ii)
Unitx(ii,ii)=1d0
Unitx(ii+Nfin/2,ii+Nfin/2)=1d0
enddo
c=== Kinetic energy in x direction for spin up
ihelp=N1
infin1=1
Do while (ihelp .Le. Nfin/2)
infin2 =ihelp
Do ii=infin1,infin2
Do jj =infin1,infin2
if( (abs(ii-jj)) .eq. 1) then
Hx(ii,jj) =V
endif
enddo
enddo
infin1 =ihelp+1
ihelp =ihelp+N1
enddo
c=== Kinetic energy in x direction for spin down
ihelp=N1+Nfin/2
infin1=Nfin/2+1
Do while (ihelp .Le. Nfin)
infin2 =ihelp
Do ii=infin1,infin2
Do jj =infin1,infin2
if( (abs(ii-jj)) .eq. 1) then
Hx(ii,jj) =V
endif
enddo
enddo
infin1 =ihelp+1
ihelp =ihelp+N1
enddo
c=== Kinetic energy in y direction for spin up
Do ii=1,Nfin/2
Do jj=1,Nfin/2
if ((abs(ii-jj)) .eq. N1) then
Hx(ii,jj) =V
endif
enddo
enddo
c=== Kinetic energy in y direction for spin down
Do ii=Nfin/2+1,Nfin
Do jj=Nfin/2+1,Nfin
if ((abs(ii-jj)) .eq. N1) then
Hx(ii,jj) =V
endif
enddo
enddo
ccc==1 and 102
ihelp=N1
infin1=1
Do while (ihelp .Le. Nfin/2)
infin2 =ihelp
Do ii=infin1,infin2
Do jj =infin1+Nfin/2,infin2+Nfin/2
if( (jj-ii) .eq. Nfin/2+1) then
Hx(ii,jj) =Rashba
Hx(jj,ii)=Rashba
endif
enddo
enddo
infin1 =ihelp+1
ihelp =ihelp+N1
enddo
c===== 101 and 2
ihelp=N1
infin1=1
Do while (ihelp .Le. Nfin/2)
infin2 =ihelp
Do ii=infin1,infin2
Do jj =infin1+Nfin/2,infin2+Nfin/2
if( (jj-ii) .eq. Nfin/2-1) then
Hx(ii,jj) =-Rashba
Hx(jj,ii) =-Rashba
endif
enddo
enddo
infin1 =ihelp+1
ihelp =ihelp+N1
enddo
c===== 11 and 101
ihelp=N1
infin1=1
Do while (ihelp .Le. Nfin/2-N1)
infin2 =ihelp
Do ii=infin1+N1,infin2+N1
Do jj =infin1+Nfin/2,infin2+Nfin/2
if(( ii .lt. jj) .and. ((abs(ii-jj)) .eq.(Nfin/2-N1)))then
Hx(ii,jj) = Imunit*Rashba
Hx(jj,ii)=-Imunit*Rashba
endif
enddo
enddo
infin1 =ihelp+1
ihelp =ihelp+N1
enddo
c==== 1 and 111
ihelp=N1
infin1=1
Do while (ihelp .Le. Nfin/2-N1)
infin2 =ihelp
Do ii=infin1+N1+Nfin/2,infin2+Nfin
Do jj =infin1,infin2
if(( ii .gt. jj) .and. ((abs(ii-jj)) .eq.(Nfin/2+N1)))then
Hx(ii,jj) = Imunit*Rashba
Hx(jj,ii)=-Imunit*Rashba
endif
enddo
enddo
infin1 =ihelp+1
ihelp =ihelp+N1
enddo
Do ii=1,nfin
Do jj=1,nfin
EHx(ii,jj)=(Etot)*Unitx(ii,jj)-Hx(ii,jj)
Hnn(ii,jj)=EHx(ii,jj)
enddo
enddo
return
end
c==========================================================
c=== Calculates self-energies connected with different wires
Subroutine Selfy(sigmR)
integer nn,mm,m,n,Nfin1,Nfin,Nle,nleads
logical logus
double precision V,al,Mass,W,Etot,hbar,rashb,rashb2
double precision Emod,AnorN1,psiN1,lstub,Wle,x
Double Complex Glp1lp1,Glp1lp1n,alpha,theta
Double Complex Glp1lp1up,G0lm1lm1up,Glp1lp1down,G0lm1lm1down
Double Complex Gxp1xp1up,Gxm1xm1up,Gxp1xp1down,Gxm1xm1down
Double Complex sigmR,kn
Double Complex Imunit,Imun0
parameter(N1=10,N2=10,Nle=10,Nfin1=N1*N2*2,nleads=8)
Parameter(pi=3.14159265358979323846264d0)
Dimension AnorN1(N1),psiN1(N1)
Dimension Glp1lp1(N1,N1)
Dimension Glp1lp1n(N1,N1)
Dimension Glp1lp1up(Nfin1,Nfin1),G0lm1lm1up(nfin1,nfin1)
Dimension Glp1lp1down(nfin1,nfin1),G0lm1lm1down(nfin1,nfin1)
Dimension Gxp1xp1up(nfin1,nfin1),Gxm1xm1up(nfin1,nfin1)
Dimension Gxp1xp1down(nfin1,nfin1),Gxm1xm1down(nfin1,nfin1)
Dimension sigmR(nleads,Nfin1,Nfin1)
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
common/stub/lstub,rashb,rashb2
common/dlead/Wle
Imunit =dcmplx(0d0,1d0)
Imun0=dcmplx(0d0,0d0)
c=============================================
Do nn =1,N1
Do mm=1,N1
Glp1lp1n(nn,mm) =dcmplx(0d0,0d0)
enddo
enddo
c=============================================
c=== (All leads in site representation)
Do ii =1,Nle
Do jj=1,Nle
Do mm=1,Nle
c mm=1
Call MODS(Emod,mm,Nle)
x=(Etot-Emod)/(2d0*V) +1d0
if (x .gt. 1d0) then
alpha = CDLOG(x+CDSQRT(Imun0+x**2-1d0))
theta =Imunit*alpha
else if (x .lt. -1d0) then
alpha = CDLOG(x+Imun0-SQRT(x**2-1d0))
theta =Imunit*alpha
else
theta =Acos((Etot-Emod)/(2d0*V)+1d0)
endif
AnorN1(mm) =(Nle*1d0/2d0+1d0/2d0*
& DBLE((1d0-EXP(Imunit*2d0*pi*mm*Nle*1d0/(Nle+1d0)))
& /(1d0-EXP(-Imunit*2d0*pi*mm*1d0/(Nle+1d0)))))**(-1d0/2d0)
psiN1(ii) = AnorN1(mm)*SIN(mm*pi*ii*1d0/(Nle+1d0))
psiN1(jj) = AnorN1(mm)*SIN(mm*pi*jj*1d0/(Nle+1d0))
Glp1lp1(ii,jj) =EXP(Imunit*THETA)/(V)
Glp1lp1n(ii,jj) =Glp1lp1n(ii,jj)+
& Glp1lp1(ii,jj)*psiN1(ii)*psiN1(jj)
enddo
c--------71 gowno =1d0
enddo
enddo
chel1=dcmplx(0d0,0d0)
c============================================
Do m=1,nfin1
Do n=1,nfin1
Glp1lp1up(m,n) =dcmplx(0d0,0d0)
G0lm1lm1up(m,n)=dcmplx(0d0,0d0)
Glp1lp1down(m,n) =dcmplx(0d0,0d0)
G0lm1lm1down(m,n)=dcmplx(0d0,0d0)
Gxp1xp1up(m,n) =dcmplx(0d0,0d0)
Gxm1xm1up(m,n)=dcmplx(0d0,0d0)
Gxp1xp1down(m,n) =dcmplx(0d0,0d0)
Gxm1xm1down(m,n)=dcmplx(0d0,0d0)
enddo
enddo
Nx=2 ! how many points in x direction in sample
c=== Horizontal leads in x direction in one indice notation
Do ii=1,N1
Do jj=1,N1
c----- w reperezentacji naturalnej, jednowskaznikowej
m =(1+ii)*N1 - 2*N1+1
n =(1+jj)*N1 - 2*N1+1
Glp1lp1up(m,n) =Glp1lp1n(ii,jj)
G0lm1lm1up(m+N1-1,n+N1-1) =Glp1lp1n(ii,jj)
Glp1lp1down(m+Nfin/2,n+Nfin/2) =Glp1lp1n(ii,jj)
G0lm1lm1down(m+Nfin/2+N1-1,n+Nfin/2+N1-1) =Glp1lp1n(ii,jj)
enddo
enddo
c=== Vertical leads in y direction in one indice notation
Do ii=1,N1
Do jj=1,N1
m=ii
n=jj
Gxp1xp1up(m,n) =Glp1lp1n(ii,jj)
Gxm1xm1up(m+Nfin/2-N1,n+Nfin/2-N1)=Glp1lp1n(ii,jj)
Gxp1xp1down(m+Nfin/2,n+Nfin/2) =Glp1lp1n(ii,jj)
Gxm1xm1down(m+Nfin-N1,n+Nfin-N1)=Glp1lp1n(ii,jj)
enddo
enddo
c=== Retarded Self-energy for 8 leads
c=== LEft spin up =1, left spin down=3; and down spin up=5, down spin up= 6 leads
c== right spin up=2, right spin down =4, top spin up =7,top spin down =8
Do i=1,nleads
Do m=1,Nfin
Do n=1,Nfin
sigmR(i,m,n)=dcmplx(0d0,0d0)
enddo
enddo
enddo
Do m =1,Nfin
Do n=1,Nfin
sigmR(1,m,n) = V**2*Glp1lp1up(m,n)
sigmR(3,m,n) = V**2*Glp1lp1down(m,n)
sigmR(5,m,n) = V**2*Gxp1xp1up(m,n)
sigmR(6,m,n) = V**2*Gxp1xp1down(m,n)
sigmR(2,m,n) =V**2*G0lm1lm1up(m,n)
sigmR(4,m,n) =V**2*G0lm1lm1down(m,n)
sigmR(7,m,n) =V**2*Gxm1xm1up(m,n)
sigmR(8,m,n) =V**2*Gxm1xm1down(m,n)
enddo
enddo
return
end
c===================================================
Subroutine Gamms(sigmR,Gamm)
integer m,n, nfin,nfin1,nleads,i
double precision V,al,MAss,W,Etot,hbar
logical logus
double precision Gamm
Double Complex sigmR
parameter(N1=10,N2=10,nfin1=N1*N2*2,nleads=8)
Dimension Gamm(nleads,nfin1,nfin1)
Dimension sigmR(nleads,nfin1,nfin1)
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
Imunit=dcmplx(0d0,1d0)
Do i=1,nleads
Do m=1,Nfin
Do n=1,Nfin
Gamm(i,m,n)=0d0
enddo
enddo
enddo
Do i=1,nleads
Do m=1,Nfin
Do n=1,Nfin
Gamm(i,m,n) =-2d0*dimag(sigmR(i,m,n))
enddo
enddo
enddo
return
end
c==================================================
Subroutine Greenji(Tpq)
c----- It calculates the transmission
c------Green function between slices j (in mode n)
c------and slice i (in mode m) by recursive Green function method
IMPLICIT NONE
integer i,j ! lattice sites
Double precision Tpq(8,8) ! matrix transmission no.of lead on no.of leads
Double precision lstub
Double precision rashb2,rashb
Double precision n2D
Integer Nfin,n,nn,mm,ii,jj,nfin1
Integer N1! no. of sites in slice k
Integer N2! no. of sites in slice k+1
Integer m,nleads,Nle
Double Complex theta
Double Complex Imunit
Double Complex alpha
double precision Gamm
Double Complex Hnn
Double Complex sigmR
Double Complex GRinv,kn
Double Complex GR
Complex GammGR
Complex GammGad
Double Precision x, rashba! Rashba parameter
Double Precision pi,dchem
Double precision V,al,Mass,W,Etot,hbar
DOUBLE PRECISION Emod
Double precision Wdis! the width of disorder
Double precision random! random number generator
Parameter(N1=10,N2=10,nfin1=N1*N2*2,Nle=10,nleads=8)
Dimension Gamm(nleads,nfin1,nfin1)
Dimension Hnn(Nfin1,Nfin1)
Dimension sigmR(nleads,nfin1,nfin1)
Dimension GRinv(nfin1,nfin1)
Dimension GR(nfin1,nfin1)
Dimension GammGad(nleads,nfin1,nfin1)
Dimension GammGR(nleads,nfin1,nfin1)
Logical logus
Parameter(pi=3.14159265358979323846264d0)
common/param/V,al,Mass,W,Etot,hbar,logus,Nfin
common/stub/lstub,rashb,rashb2
OPEN(UNIT=88,file='Hamilton.dat')
OPEN(Unit=89,file='Grinv.dat')
Open(unit=91,file='selfy1.dat')
open(unit=92,file='selfy2.dat')
open (unit=93,file= 'smat.dat')
rashba=rashb
c==== Assumption of electron concentration
c==== Half of the band occupied n2D=100el/100*100nm^{2}
c n2D=1d0*1d12 ![1/cm^2]
c n2D=n2D/1d11
c dchem=(0.24d0*n2D/5d-2)/1d3 ! [eV]
Imunit =dcmplx(0d0,1d0)
CAll Hamiltonian(Hnn)
Call Selfy(sigmR)
Call Gamms(sigmR,Gamm)
Do i=1,nleads
Do m=1,Nfin
Do n=1,Nfin
GammGR(i,m,n)=cmplx(0d0,0d0)
GammGAd(i,m,n)=cmplx(0d0,0d0)
enddo
enddo
enddo
Do i=1,nleads
Do j=1,nleads
Tpq(i,j) =0d0
enddo
enddo
Do m=1,Nfin
Do n=1,Nfin
GRinv(m,n)=dcmplx(0d0,0d0)
enddo
enddo
c==Inverse retarded Green functions for sample included effect of leads
Do m=1,Nfin
Do n=1,Nfin
GRinv(m,n) =Hnn(m,n)
enddo
enddo
Do m=1,Nfin
Do n=1,Nfin
Do i=1,nleads
GRinv(m,n)=Grinv(m,n)-sigmR(i,m,n)
enddo
enddo
enddo
CALL inv1(GRinv,GR,Nfin)
c================================================
c== Transmissions to electrodes 1 and 3,
c== left spin up and left spin down electrodes
Do i=1,nleads
Do n=1,nfin
Do m=1,Nfin
Do nn=1,Nfin
GammGR(i,n,m)=GammGR(i,n,m)+Gamm(i,n,nn)*GR(nn,m)
GammGad(i,n,m) =GammGad(i,n,m)+Gamm(i,n,nn)*CONJG(GR(m,nn))
enddo
enddo
enddo
enddo
Do i=1,nleads
Do j=1,nleads
Do n=1,Nfin
Do m=1,Nfin
Tpq(i,j)=Tpq(i,j)+GammGR(i,n,m)*GammGad(j,m,n)
enddo
enddo
enddo
enddo
DO i=1,nleads
Do n=1,Nfin
Tpq(i,i) =Tpq(i,i)-Imunit*GammGR(i,n,n)
& +Imunit*GammGad(i,n,n)
enddo
enddo
Do nn=1,Nle
Call Mods(Emod,nn,Nle)
Call Findk(Emod,kn)
If (dimag(kn) .Eq. 0d0) then
Do i=1,nleads
Tpq(i,i) =Tpq(i,i)+1d0
enddo
endif
enddo
return
end
c vim: ignorecase