Oscillatory electron phonon coupling in Pb/Si（111）deduced by temperature-dependent quantum well states  

作　　者：张艳锋 贾金锋 韩铁柱 唐喆 沈全通 郭阳 薛其坤 

机构地区：[1]Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, The Chinese Academy of Sciences, Beijing 100080, China

出　　处：《Chinese Physics B》2005年第9期1910-1914,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation （Grant Nos 60021403, 60325415, 60128404） and the Special Funds for Major State Basic Research Program （Grant Nos G001CB3095, 2002CB613502, 2004CB720608） of Ministry of Science and Technology of China.

摘　　要：Photoemission study of atomically flat Pb films with a thickness from 15 to 24 monolayers （ML） have been performed within a temperature range 75-270K. Well-defined quantum well states （QWSs） are observed, which exhibit interesting temperature-dependent behaviours. The peak position of the QWSs shifts towards higher binding energy with increasing substrate temperature, whereas the peak width broadens linearly due to enhanced electron-phonon coupling strength （λ）. An oscillatory A with a period of 2ML is deduced. Preliminary analysis shows that the oscillation can be explained in terms of the interface induced phase variations, and is thus a manifestation of the quantum size effects.Photoemission study of atomically flat Pb films with a thickness from 15 to 24 monolayers （ML） have been performed within a temperature range 75-270K. Well-defined quantum well states （QWSs） are observed, which exhibit interesting temperature-dependent behaviours. The peak position of the QWSs shifts towards higher binding energy with increasing substrate temperature, whereas the peak width broadens linearly due to enhanced electron-phonon coupling strength （λ）. An oscillatory A with a period of 2ML is deduced. Preliminary analysis shows that the oscillation can be explained in terms of the interface induced phase variations, and is thus a manifestation of the quantum size effects.

关 键 词：Pb thin films PHOTOEMISSION quantum well states electron-phonon interactions 

分 类 号：O484.4[理学—固体物理] O482.7[理学—物理]