2020/02/28 by Yanan Li, Christian Parsons, Li, Yanan +14
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Topological Materials and Phenomena #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.2002.12546
openalex publication_date 2020/02/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We report an anomalous electronic transition at 140~K in high-quality Bi2Se3, where charge order emerges in a defect-tuned system. Native defects (Se vacancies and Bi intercalation)-intrinsic to our reproducible growth method-modulate electronic states without compromising sample integrity, mirroring doping-induced phases in correlated topological materials. The hexagonally deformed Fermi surfaces and strong nesting in Bi2Se3 and related compounds (such as, Bi2Te3 ) have long suggested the possibility of density wave ordering, with recent work on superconducting Cu- and Nb-doped Bi2Se3 further highlighting charge order's role in unconventional superconductivity. Here, we identify a periodic lattice distortion near room temperature via electron diffraction, consistent with diffuse charge order. This is accompanied by a 140~K electronic transition, manifested in resistivity measurements as a pronounced anomaly, exhibiting a semiconductor-like upturn, signaling the opening of an energy gap. Nuclear magnetic resonance (NMR) studies of the 209Bi spin-lattice relaxation rate (1/T1 ) reveal a concurrent transition, confirming the emergence of an 8~meV energy gap. Our results are consistent with defect-stabilized charge order in Bi2Se3 , linking native defects to its electronic properties and offering broader insights into the interplay between charge order and superconductivity in topological materials.