Quantum Oscillations in a Two-Dimensional Electron Gas at the Rocksalt/Zincblende Interface of PbTe/CdTe (111) Heterostructures
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- 作者：Bingpo Zhang ; Ping Lu ; Henan Liu ; Lin Jiao ; Zhenyu Ye ; M. Jaime ; F.F. Balakirev ; Huiqiu Yuan ; Huizhen Wu ; Wei Pan ; Yong Zhang
- 刊名：Nano Letters
- 出版年：2015
- 出版时间：July 8, 2015
- 年：2015
- 卷：15
- 期：7
- 页码：4381-4386
- 全文大小：313K
- ISSN：1530-6992
文摘
Quantum oscillations are observed in the 2DEG system at the interface of novel heterostructures, PbTe/CdTe (111), with nearly identical lattice parameters (aPbTe = 0.6462 nm, aCdTe = 0.648 nm) but very different lattice structures (PbTe: rock salt, CdTe: zinc blende). The 2DEG formation mechanism, a mismatch in the bonding configurations of the valence electrons at the interface, is uniquely different from the other known 2DEG systems. The aberration-corrected scanning transmission electron microscope (AC-STEM) characterization indicates an abrupt interface without cation interdiffusion due to a large miscibility gap between the two constituent materials. Electronic transport measurements under magnetic field up to 60 T, with the observation of Landau level filling factor 谓 = 1, unambiguously reveal a 蟺 Berry phase, suggesting the Dirac Fermion nature of the 2DEG at the heterostructure interface, and the PbTe/CdTe heterostructure being a new candidate for 2D topological crystalline insulators.