Exceptional electronic transport and quantum oscillations in thin bismuth crystals grown inside van der Waals materials

• DOI: 10.48550/arxiv.2211.07681
• Publication Date: 2022-01-01
• Authors: Laisi Chen; Amy X. Wu; Naol Tulu; Joshua Wang; Adrian Juanson; Kenji Watanabe; Takashi Taniguchi; Michael T. Pettes; Marshall Campbell; Chaitanya Gadre; Yinong Zhou; Hangman Chen; Penghui Cao; Luis A. Jauregui; Ruqian Wu; Xiaoqing Pan; Javier Sanchez-Ya...
• Keywords: Bismuth; Nanometre; Bismuth telluride; Topological insulator; Surface States

Confining materials to two-dimensional forms changes the behavior of electrons and enables new devices. However, most are challenging produce as uniform thin crystals. Here, we present a synthesis approach where crystals grown in nanoscale mold defined by atomically-flat van der Waals (vdW) materials. By heating compressing bismuth vdW made hexagonal boron nitride (hBN), grow ultraflat less than 10 nanometers thick. Due quantum confinement, bulk states gapped, isolating intrinsic Rashba surface for transport studies. The vdW-molded shows exceptional electronic transport, enabling observation Shubnikov-de Haas oscillations originating from (111) state Landau levels, which have eluded previous measuring gate-dependent magnetoresistance, observe multi-carrier level splitting, with features both top bottom surfaces. Our vdW-mold growth technique establishes platform studies control bismuth's topological boundary modes. Beyond bismuth, vdW-molding provides low-cost way synthesize ultrathin directly integrate them into heterostructure.