Nature of the 1/f Noise in Graphene, Direct Evidence for the Mobility Fluctuations Mechanism

Adil Rehman; Juan Antonio Delgado Notario; Juan Salvador Sanchez; Yahya Moubarak Meziani; Grzegorz Cywiński; Wojciech Knap; Alexander A. Balandin; Michael Levinshtein; Sergey Rumyantsev

arXiv · 2111.04119

Nature of the 1/f Noise in Graphene, Direct Evidence for the Mobility Fluctuations Mechanism

Adil Rehman·Juan Antonio Delgado Notario·Juan Salvador Sanchez·Yahya Moubarak Meziani·Grzegorz Cywiński·Wojciech Knap·Alexander A. Balandin·Michael Levinshtein·Sergey Rumyantsev

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Abstract

The nature of the low-frequency current fluctuations, i.e. carrier number vs. mobility, defines the strategies for noise reduction in electronic devices. While the 1/f noise in metals has been attributed to the electron mobility fluctuations, the direct evidence is lacking (f is the frequency). Here we measured noise in h-BN encapsulated graphene transistor under the condition 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 uB=1 (u is the electron mobility). This observation proves unambiguously that the mobility fluctuations are the dominant mechanism of the 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.

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Adil Rehman, Juan Antonio Delgado Notario, Juan Salvador Sanchez, Yahya Moubarak Meziani, Grzegorz Cywiński, Wojciech Knap, Alexander A. Balandin, Michael Levinshtein, Sergey Rumyantsev. 2021-11-07. Nature of the 1/f Noise in Graphene, Direct Evidence for the Mobility Fluctuations Mechanism. https://arxiv.org/abs/2111.04119

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