• 文献标题:   Tunable bandwidths and gaps in twisted double bilayer graphene on the verge of correlations
  • 文献类型:   Article
  • 作  者:   ADAK PC, SINHA S, GHORAI U, SANGANI LDV, WATANABE K, TANIGUCHI T, SENSARMA R, DESHMUKH MM
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   Tata Inst Fundamental Res
  • 被引频次:   8
  • DOI:   10.1103/PhysRevB.101.125428
  • 出版年:   2020

▎ 摘  要

We use temperature-dependent resistivity in small-angle twisted double bilayer graphene to measure bandwidths and gaps of the bands. This electron-hole asymmetric system has one set of nondispersing bands that splits into two flat bands with the electric field-distinct from the twisted bilayer system. With electric field, the gap between two emergent flat bands increases monotonically and bandwidth is tuned from 1 to 15 meV. These two flat bands with gap result in a series of thermally induced insulator to metal transitions-we use a model, at charge neutrality, to measure the bandwidth using only transport measurements. Having two flat bands with tunable gap and bandwidth offers an opportunity to probe the emergence of correlations.