一维声学极化子自陷判据的重新确立  

Reestablished the Criterion of Self-trapping Transition of One Dimensional Acoustic Polaron

作　　者：段晓峰[1] 侯俊华[1] DUAN Xiaofeng;HOU Junhua(College of Physics and Information Engineering,Shanxi Normal University,041004,Linfen,Shanxi,PRC)

机构地区：[1]山西师范大学物理与信息工程学院,山西临汾041004

出　　处：《江西科学》2018年第2期206-208,243,共4页Jiangxi Science

基　　金：国家自然科学基金(编号:11147159);山西省高等学校科技创新项目(编号20161104)

摘　　要：从描述一维晶格振动的"简谐近似"描述出发,考虑电子-声学声子的库伦型相互作用,从源头推导得到了新的描述一维电子-声学声子耦合的哈密顿量。采用类Huybrechts变分法讨论了一维声学极化子自陷的可能性。结果表明:一维声学极化子由自由态向自陷态转变对应的临界电子-声子耦合常数随声子截止波矢的增大而减小;一维声学极化子自陷比二维和三维情况要容易。The Hamiltonian of electron-acoustic phonon interaction in one dimensional system is derived.The criterion of the self-trapping transition of the one dimensional acoustic polaron is investigated by the Huybrechts-like variational approach.It is indicated that the position of the critical point is sensitive to the cutoff wave-vector and moves also toward the direction of smaller e-p coupling with the increasing cutoff wave vector.The self-trapping transition of the acoustic polaron in one dimensional system is easier than that in two and three dimensional systems.

关 键 词：一维声学极化子 电子-声学声子耦合 自陷转变 

分 类 号：O471.3[理学—半导体物理]