Quantum oscillations in Pb/Si (111) heterostructure system
Quantum oscillations in Pb/Si (111) heterostructure system
ZHANG Yan-feng1, LI Shao-chun1, MA Xu-cun1, JIA Jin-feng1, XUE Qi-kun2
1.Institute of Physics, Chinese Academy of Science, Beijing 100080, China; 2.Institute of Physics, Chinese Academy of Science, Beijing 100080, China; Department of Physics, Tsinghua Univeristy, Beijing 100084, China
Abstract：This paper summarizes our recent work on the study of quantum size effects (QSE) and novel physical properties of the Pb/Si (111) heterostructure. Two different types of samples were investigated. One is wedge-shaped Pb islands, and the other is atomically flat Pb thin films. With scanning tunneling microscopy (STM) manipulation, we observed an intriguing morphology dynamics of the islands that swings between two extreme energy states, like that in a classical pendulum. We show that the dynamics is a result of the competition between the QSE and the classical step free energy minimizing effect. For the second type of the samples, the QSE is studied in terms of thickness-dependent film stability, electronic structure and physical properties by using STM, angle-resolved photoemission spectroscopy (ARPES) and transport measurement. The results consistently reveal the formation of quantum well states (QWS) due to electron confinement in the films. This size effect could greatly modify the electronic structure near the Fermi level and lead to quantum oscillations in superconductivity, electron-phonon coupling and thermal expansion. The work unambiguously demonstrates the possibility of quantum engineering of physical properties of thin films by exploiting well-controlled and thickness-dependent QSE.
出版日期: 2006-09-05
引用本文:
. Quantum oscillations in Pb/Si (111) heterostructure system[J]. Frontiers of Physics in China - Selected Publications from Chinese Universities, 2006, 1(3): 323-333.
ZHANG Yan-feng, LI Shao-chun, MA Xu-cun, JIA Jin-feng, XUE Qi-kun. Quantum oscillations in Pb/Si (111) heterostructure system. Front. Phys. , 2006, 1(3): 323-333.
