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Updated: Aug 22, 2025

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Multifractal Conductance Fluctuations in High-Mobility Graphene in the Integer Quantum Hall Regime
Kazi Rafsanjani Amin1, Ramya Nagarajan1, Rahul Pandit1
1Department of Physics, Indian Institute of Science, Bangalore, Karnataka 560012, India.
Abstract:
We present the first experimental evidence for the multifractality of a transport property at a topological phase transition. In particular, we show that conductance fluctuations display multifractality at the integer quantum Hall plateau-to-plateau transitions in high-mobility mesoscopic graphene devices. The multifractality gets rapidly suppressed as the chemical potential moves away from these critical points. Our combination of experimental study and multifractal analysis provides a novel method for probing the criticality of wave functions at phase transitions in mesoscopic systems, and quantum criticality in several condensed-matter systems.
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