[Pw_forum] Left and right going Bloch's states from PWCOND

[Manoj Srivastava]

Dear All, 
 I am trying to figure out the left and right going Bloch's states in the
lead from PWCOND. For a given (kx,ky)and energy we get kz. The code only
prints out Bloch's state moving in one direction. eg. in one of the
calculation- 
k//=(0.375,-0.375)
 Nchannels of the left tip =            1
        k1(2pi/a)    k2(2pi/a)       E-Ef (eV)

   0.3157801   0.0000000   0.0000000

Now if I want Bloch's state moving in right as well as left direction, I
can go to kbloch.f90 subroutine, and print out all the eigen values of
AX=exp(ikd)BX, and out of those the ones with real solution would be our
Bloch's state, so I get for each channel two solutions- 
 kval (-0.275409421993275,1.823688001395235E-010)
 kval (0.315780119742506,-3.611201785292708E-012)

To figure out the direction, I can calculate current associated with these
Bloch's sate and if the current is +ive it is right moving , and if '-'ive
its left moving Bloch's state. I can print out current from jbloch.f90
subroutine which are - 
 current eigenvalue -1.86502143831863  1.59149029314457

So, clearly the first state with kval=-0.2754094 is left moving and the
other one right moving. Upto here its clear to me how to identify left and
right moving states.

I get confused when for a given (kx,ky,E), I have more than one Bloch'
state. In another calculation where i get multiple Bloch's state- 
 Nchannels of the left tip =            5
        k1(2pi/a)    k2(2pi/a)       E-Ef (eV)

  -0.0746301   0.0000000   0.0000000
   0.1205527   0.0000000   0.0000000
   0.3112908   0.0000000   0.0000000
   0.4200218   0.0000000   0.0000000
  -0.4935150   0.0000000   0.0000000

so i did the same trick i did above to first print out kz and then
current, which gives me - 
 kval (-0.420023481074359,1.979595081419732E-010)    (call it a)
 kval (0.420023367986768,2.500979698670295E-011)      (b)
 kval (-0.306507431678779,-1.236804629184431E-011)    (c)
 kval (-0.125376071175573,-6.134512510438736E-011)    (d)
 kval (-7.945001124706894E-002,6.683546930037856E-011)(e)
 kval (0.106554601758169,-6.427946951285107E-011)     (f)
 kval (8.866867725358024E-002,8.342250371574646E-011) (g)
 kval (0.325333314672671,1.260810749228185E-011)      (h)
 kval (-0.488725859521576,1.769197678346003E-010)     (i)
 kval (0.479509832763231,1.765499400037283E-010)      (j)

current eigenvalue  -9.31389492882581       -1.24296522993488
  -1.21324078359658       -1.11950286753963       -1.08166842367443
   1.08187482164864        1.11973146584263        1.21295295042188
   1.24280031534940        9.313897787790

So, the first 5 are left moving and rest are right moving. But I dont know
the pairs. for example for left moving state a, what is the corresponding
right moving state whether its f or g ... j ?

Any help would be appreciated. 

Regards, 
Manoj Srivastava
University of Florida, Gainesville.