High-resolution angle-resolved photoemission studies of quasiparticle dynamics in graphite

Abstract

We obtained the spectral function of the graphite H point using high resolution angle resolved photoelectron spectroscopy (ARPES). The extracted width of the spectral function (inverse of the photo-hole lifetime) near the H point is approximately proportional to the energy as expected from the linearly increasing density of states (DOS) near the Fermi energy. This is well accounted by our electron-phonon coupling theory considering the peculiar electronic DOS near the Fermi level. And we also investigated the temperature dependence of the peak widths both experimentally and theoretically. The upper bound for the electron-phonon coupling parameter is 0.23, nearly the same value as previously reported at the K point. Our analysis of temperature dependent ARPES data at K shows that the energy of phonon mode of graphite has much higher energy scale than 125K which is dominant in electron-phonon coupling.

The surface relaxation and band structure of Mo(112)

“…Obviously, there is now a large body of evidence that electron-phonon coupling can affect the band structure, particularly in the region of the Fermi level [1][2][3]. The resulting mass enhancement factors have not only now been characterized for a whole host of metal surfaces [1], but also for the surfaces of a semimetal like graphite [72] and the surface of a superconductor like 2H-NbS 2 [73]. As noted at the outset of this article, there is a strong interplay between the shifts in the surface band structure due to electronphonon coupling and the surface phonon spectra.…”

Anisotropy of π-Plasmon Dispersion Relation of AA-Stacked Graphite

“…29−31) By the way, there were experiments to stress the influences of the stacking effect on physical properties. For examples: (1) angleresolved photoemission (ARPES) was used to study electron-electron correlations, 32) (2) high-resolution ARPES was performed to study quasiparticle dynamics, 33) and (3) the measurements of inelastic X-ray scattering on the spectra near Bragg reflections.…”

Giant spin rotation under quasiparticle-photoelectron conversion: Joint effect of sublattice interference and spin-orbit coupling

“…We emphasize that this is impossible for simple lattices, where ͗ŝ͘ 2 = 1 is maintained either by in-plane polarization 15 or by out-of-plane spin rotation, as recently reported. 16 While the effect of sublattice interference on the angular dependence of ARPES, unveiled by Shirley et al, 13 is well documented for monolayer 10,12 and bilayer 12,17 graphene and for graphite, 13,[18][19][20] the recent progress in studying quasiparticles by SARPES techniques, the novelty of results, and the large magnitude of spin-orbit coupling found in a number of systems 10,16,[21][22][23][24][25][26][27][28][29] all call for proper understanding of interference-generated spin patterns in photoemission. They are specific for the single-step transformation of Bloch spinors of quasiparticles into photoelectron plane waves with large in-plane ͑Brillouin͒ momentum and manifest themselves in singular k dependencies in the k → 0 limit.…”