Fitxers
Tipus de document
ArticleVersió
Versió publicadaData de publicació
Tots els drets reservats
Si us plau utilitzeu sempre aquest identificador per citar o enllaçar aquest document: https://hdl.handle.net/2445/9828
Nonlocal exchange effects on the bulk plasmon dispersion relation
Títol de la revista
Director/Tutor
ISSN de la revista
Títol del volum
Recurs relacionat
Resum
Starting from the action principle, a bulk plasmon dispersion relation is obtained. We work with Slater determinants built of plane waves and consider a Hermitian generator of plasma oscillations (with well-defined q momentum) S=αQ-βP, where Q=
tsum
j
cos(q⋅
x
j
) is a time-even Hermitian generator, P=scrB
tsum
j
[
p
j
⋅q sin(q⋅
x
j
)+sin(q⋅
x
j
)
p
j
⋅q] is a time-odd Hermitian generator, α(t) and β(t) are real time-dependent functions, and scrB is a real normalization constant. If the parameters α and β are small, the amplitude of the plasma oscillations generated by S is small. The quantum-mechanical action principle leads, in the harmonic approximation, to a quadratic Lagrangian
L
(
2
)
(α,β) from which the dispersion relation is obtained. The nonlocal expression of the exchange contribution is explicitly obtained. The resulting bulk plasmon dispersion relation is related to the energy-weighted and cubic-energy-weighted sum rules. Finally, we compare our results with the experimental data.
Matèries
Matèries (anglès)
Citació
Citació
JOÃO DA PROVIDÊNCIA, Jr. and BARBERÁN FALCÓN, Núria. Nonlocal exchange effects on the bulk plasmon dispersion relation. Physical Review B. 1992. Vol. 45, num. 12, pags. 6935-6937. ISSN 0163-1829. [consulted: 29 of June of 2026]. Available at: https://hdl.handle.net/2445/9828