Unveiling mode-selected electron-phonon interactions in metal films by helium atom scattering

被引：40

作者：

Benedek, G. ^{[1
,2
,3
]}

Bernasconi, M. ^{[2
]}

Bohnen, K. -P. ^{[4
]}

Campi, D. ^{[2
]}

Chulkov, E. V. ^{[1
,5
,6
,7
]}

Echenique, P. M. ^{[1
,5
,6
]}

Heid, R. ^{[4
]}

Sklyadneva, I. Yu. ^{[1
,7
]}

Toennies, J. P. ^{[3
]}

机构：

[1] DIPC, Donostia San Sebastian 20018, Spain

[2] Univ Milano Bicocca, Dipartimento Sci Mat, I-20125 Milan, Italy

[3] Max Planck Inst Dynam & Selbstorg, D-37073 Gottingen, Germany

[4] Karlsruher Inst Technol, Inst Festkorperphys, D-76021 Karlsruhe, Germany

[5] Univ Basque Country, Euskal Herriko Unibertsitatea, Dept Fis Mat, E-20018 Donostia San Sebastian, Spain

[6] Univ Basque Country, Euskal Herriko Unibertsitatea, CFM CSIC UPV EHU, E-20018 Donostia San Sebastian, Spain

[7] Tomsk State Univ, Tomsk 634050, Russia

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2014年 / 16卷 / 16期

关键词：

SURFACE SCATTERING; SUPERCONDUCTIVITY; DENSITY; ENERGY; EXCITATION; HE; BI;

D O I：

10.1039/c3cp54834a

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The quasi two-dimensional electron gas on a metal film can transmit to the surface even minute mechanical disturbances occurring in the depth, thus allowing the gentlest of all surface probes, helium atoms, to perceive the vibrations of the deepest atoms via the induced surface-charge density oscillations. A density functional perturbation theory (DFPT) and a helium atom scattering study of the phonon dispersion curves in lead films of up to 7 mono-layers on a copper substrate show that: (a) the electron-phonon interaction is responsible for the coupling of He atoms to in-depth phonon modes; and (b) the inelastic HAS intensity from a given phonon mode is proportional to its electron-phonon coupling. The direct determination of mode-selected electron-phonon coupling strengths has great relevance for understanding superconductivity in thin films and two-dimensional systems.

引用

页码：7159 / 7172

页数：14

共 65 条

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[Anonymous], 1991, J PHYS CONDENS MATTE

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