It is currently Sat Jan 18, 2020 2:49 pm

Tell a friend!


Post new topic Reply to topic  [ 1 post ] 
Phonon linewidth constant 0 at Gamma for a metal? 
Author Message
User avatar

Joined: Thu Jul 14, 2016 6:09 am
Posts: 37
University: POSTECH (Korea)
Post Phonon linewidth constant 0 at Gamma for a metal?
Dear all,

I have a strange problem: I have a metallic slab (Ag 100). When I calculate the electron-phonon coupling and phonon linewidth the latter is always constant 0 at q1=Gamma. Away from gamma (even a small step is enough q2=0.01 |Gamma-X|) this is no longer the case as you can see below.

Code:
# Phonon frequency and phonon lifetime in meV
# Q-point  Mode   Phonon freq (meV)   Phonon linewidth (meV)
        1     1      0.14018096E-05      0.0000000000E+00
        1     2      0.15037978E-05      0.0000000000E+00
        1     3      0.15678200E-05      0.0000000000E+00
        1     4      0.32037347E+01      0.0000000000E+00
        1     5      0.32037347E+01      0.0000000000E+00
        1     6      0.50111038E+01      0.0000000000E+00
        1     7      0.50111038E+01      0.0000000000E+00
        1     8      0.52040993E+01      0.0000000000E+00
        1     9      0.80325952E+01      0.0000000000E+00
        1    10      0.80325952E+01      0.0000000000E+00
        1    11      0.81943124E+01      0.0000000000E+00
        1    12      0.10998395E+02      0.0000000000E+00
        1    13      0.10998395E+02      0.0000000000E+00
        1    14      0.12627565E+02      0.0000000000E+00
        1    15      0.12627565E+02      0.0000000000E+00
        1    16      0.12875931E+02      0.0000000000E+00
        1    17      0.16689456E+02      0.0000000000E+00
        1    18      0.18803622E+02      0.0000000000E+00
        1    19      0.25815292E+02      0.0000000000E+00
        1    20      0.25815292E+02      0.0000000000E+00
        1    21      0.32939073E+02      0.0000000000E+00
        1    22      0.52623817E+02      0.0000000000E+00
        1    23      0.52623817E+02      0.0000000000E+00
        1    24      0.54967801E+02      0.0000000000E+00
        1    25      0.54967801E+02      0.0000000000E+00
        1    26      0.57559031E+02      0.0000000000E+00
        1    27      0.64030663E+02      0.0000000000E+00
        2     1     -0.57327299E+00      0.0000000000E+00
        2     2      0.50717746E-01      0.0000000000E+00
        2     3      0.52337994E+00      0.0000000000E+00
        2     4      0.31996073E+01      0.1518331503E-03
        2     5      0.32052218E+01      0.1518331503E-03
        2     6      0.49762293E+01      0.1529582313E-01
        2     7      0.50116566E+01      0.9400167807E-05
        2     8      0.52458229E+01      0.1173353266E+00
        2     9      0.80309468E+01      0.1160566942E-02
        2    10      0.80326033E+01      0.1160566942E-02


mode 9 for example has \omega_{q\nu}=8 meV; there is plenty of "DOS" 8 meV above Ef for vertical (q=0) transitions in my system and I think the first equation here: http://epw.org.uk/Documentation/Electron-phononCoupling should definitely yield some non-zero elements;

I have tested different values for degaussq/w but above behaviour does not change.

Your help is very much appreciated!

Best,
Chris
Since a metal has plenty of states below and above Ef I was curious why the linewidth would be constant 0 in this case - did I do something wrong?


Mon Sep 30, 2019 6:42 am
Profile E-mail
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1 post ] 


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
cron
Powered by phpBB © phpBB Group.
Designed by Vjacheslav Trushkin

(All content on this board is governed by and is the sole responsibility of the board administrator.)


Gratis forum Free forum hosting| gratis phpbb3 forum | phpbb3 styles