Importance of vertex corrections for obtaining correct selection rules in the theory of photoemission
(1986) In Physical Review B 34(6). p.37983806 Abstract
 It is shown that the commonly used approximation for the noloss angleresolved photocurrent from solids in general violates the optical selection rules if the finalstate inverse lowenergy electron diffraction orbital is taken to be damped. The violations occur in the velocity formula, which is inconsistent with the corresponding and commonly used acceleration formula in which the matrix elements are evaluated with respect to the gradient of the oneelectron potential. It has recently been shown that, in a correct description of the noloss photocurrent, the bare matrix elements should be replaced by the appropriate vectorcoupling vertex function. We demonstrate that this modification is needed in order to have correct selection rules... (More)
 It is shown that the commonly used approximation for the noloss angleresolved photocurrent from solids in general violates the optical selection rules if the finalstate inverse lowenergy electron diffraction orbital is taken to be damped. The violations occur in the velocity formula, which is inconsistent with the corresponding and commonly used acceleration formula in which the matrix elements are evaluated with respect to the gradient of the oneelectron potential. It has recently been shown that, in a correct description of the noloss photocurrent, the bare matrix elements should be replaced by the appropriate vectorcoupling vertex function. We demonstrate that this modification is needed in order to have correct selection rules and consistency between the velocity and acceleration formulas for photoemission and photoabsorption. Our formalism further allows us to interpret the commonly used acceleration formula in terms of a welldefined approximation which leaves out localfield effects, and to give approximations which obey the selection rules. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/record/8773866
 author
 Almbladh, CarlOlof ^{LU}
 organization
 publishing date
 1986
 type
 Contribution to journal
 publication status
 published
 subject
 in
 Physical Review B
 volume
 34
 issue
 6
 pages
 3798  3806
 publisher
 American Physical Society
 external identifiers

 Scopus:26344449409
 ISSN
 1550235X
 language
 English
 LU publication?
 yes
 id
 e119283a5a1e4d37b7c61a66c9182c5a (old id 8773866)
 date added to LUP
 20160227 01:06:21
 date last changed
 20160416 12:08:55
@misc{e119283a5a1e4d37b7c61a66c9182c5a, abstract = {It is shown that the commonly used approximation for the noloss angleresolved photocurrent from solids in general violates the optical selection rules if the finalstate inverse lowenergy electron diffraction orbital is taken to be damped. The violations occur in the velocity formula, which is inconsistent with the corresponding and commonly used acceleration formula in which the matrix elements are evaluated with respect to the gradient of the oneelectron potential. It has recently been shown that, in a correct description of the noloss photocurrent, the bare matrix elements should be replaced by the appropriate vectorcoupling vertex function. We demonstrate that this modification is needed in order to have correct selection rules and consistency between the velocity and acceleration formulas for photoemission and photoabsorption. Our formalism further allows us to interpret the commonly used acceleration formula in terms of a welldefined approximation which leaves out localfield effects, and to give approximations which obey the selection rules.}, author = {Almbladh, CarlOlof}, issn = {1550235X}, language = {eng}, number = {6}, pages = {37983806}, publisher = {ARRAY(0x8e9f320)}, series = {Physical Review B}, title = {Importance of vertex corrections for obtaining correct selection rules in the theory of photoemission}, volume = {34}, year = {1986}, }