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Quantum Hall Effect at 40 kelvin: Evidence of MacroscopicQuantization in the Extreme Soft Limit

Timir Datta·Michael Bleiweiss·Anca Lungu·Ming Yin·Zafar Iqbal
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Abstract

Evidence of both fractional and integer quantum hall effects (QHE) in three dimensional bulk replica opal (250nm diameter) structures of non-crystalline carbon are presented. In a remarkably soft quantum limit of ~ 40K temperature and about one tesla of magnetic field clear hall steps, such as n= 2/3, 4/5, 1 and others were observed to be coordinated with the minima of longitudinal magneto-resistance. This behavior is indicative of macroscopic quantum phenomenon associated with electronic condensation into a strongly correlated quantum liquid (QL). For other systems, such as very high mobility, two-dimensional, electron (hole)-gas or (TDEG) these effects typically arise under high magnetic fields (B) and at low temperatures (T), i.e., in the extreme quantum limit (B/T>1). Currently, QHE is applied as calibration benchmark, international resistance standard, and a characterization technique for semiconductor heterostructures. We believe that applications can be widespread if the devices and the operating conditions were more accessible.

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Timir Datta, Michael Bleiweiss, Anca Lungu, Ming Yin, Zafar Iqbal. 2005-03-07. Quantum Hall Effect at 40 kelvin: Evidence of MacroscopicQuantization in the Extreme Soft Limit. https://arxiv.org/abs/cond-mat/0503166

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