Nature of the 1/f noise in graphene—direct evidence for the mobility fluctuation mechanism. Issue 19 (6th May 2022)

• Record Type: Journal Article
• Authors: Rehman, Adil; Delgado Notario, Juan Antonio; Salvador Sanchez, Juan; Meziani, Yahya Moubarak; Cywiński, Grzegorz; Knap, Wojciech; Balandin, Alexander A.; Levinshtein, Michael; Rumyantsev, Sergey
• Is Part Of: Nanoscale. Volume 14:Issue 19(2022)
• Page Start: 7242
• Page End: 7249
• Publication Date: 2022-05-06
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d2nr00207h
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : Measurements under conditions of geometrical magnetoresistance prove that 1/ f noise in graphene is dominated by mobility fluctuations. Abstract : The nature of the low-frequency 1/ f noise in electronic materials and devices is one of the oldest unsolved physical problems ( f is the frequency). The fundamental question of the noise source—fluctuations in the mobility vs . number of charge carriers—is still debated. While there are several pieces of evidence to prove that the 1/ f noise in semiconductors is due to the fluctuations in the number of the charge carriers, there is no direct evidence of the mobility fluctuations as the source of 1/ f noise in any material. Herein, we measured noise in an h -BN encapsulated graphene transistor under the conditions of geometrical magnetoresistance to directly assess the mechanism of low-frequency electronic current fluctuations. It was found that the relative noise spectral density of the graphene resistance fluctuations depends non-monotonically on the magnetic field ( B ) with a minimum at approximately μ 0 B ≅ 1 ( μ 0 is the electron mobility). This observation proves unambiguously that mobility fluctuations are the dominant mechanism of electronic noise in high-quality graphene. Our results are important for all proposed applications of graphene in electronics and add to the fundamental understanding of the 1/ f noise origin in any electronic device.