• 文献标题:   Noise in Graphene Super lattices Grown on Hexagonal Boron Nitride
  • 文献类型:   Article
  • 作  者:   LI XF, LU XB, LI TY, YANG W, FANG JM, ZHANG GY, WU YQ
  • 作者关键词:   graphene, boron nitride, superlattice, transistor, low frequency noise
  • 出版物名称:   ACS NANO
  • ISSN:   1936-0851 EI 1936-086X
  • 通讯作者地址:   Huazhong Univ Sci Technol
  • 被引频次:   9
  • DOI:   10.1021/acsnano.5b05283
  • 出版年:   2015

▎ 摘  要

Existing in almost all electronic systems, the current noise spectral density, originated from the fluctuation of current, is by nature far more sensitive than the mean value of current, the most common characteristic parameter in electronic devices. Existing models on its origin of either carrier number or mobility are adopted in practically all electronic devices. For the past few decades, there has been no experimental evidence for direct association between 1/f noise and any other kinetic phenomena in solid state devices. Here, in the study of a van der Waals heterostructure of graphene on hexagonal BN superlattice, satellite Dirac points have been characterized through 1/f noise spectral density with pronounced local minima and asymmetric magnitude associated with its unique energy dispersion spectrum, which can only be revealed by scanning tunneling microscopy and low temperature magneto-transport measurement. More importantly, these features even emerge in the noise spectra of devices showing no minima in electric current, and are robust at all temperatures down to 4.3 K. In addition, graphene on h-BN exhibits a record low noise level of 1.6 x 10(-9) mu m(2) Hz(-1) at 10 Hz, more than 1 order of magnitude lower than previous results for graphene on SiO2. Such an epitaxial van der Waals material system not only enables an unprecedented characterization of fundamentals in solids by 1/f noise, but its superior interface also provides a key and feasible solution for further improvement of the noise level for graphene devices.