quantum Hall effect tagged posts

‘Beautiful Marriage’ of Quantum Enemies

Doctoral students Phillip Dang (left) and Reet Chaudhuri at the National High Magnetic Field Laboratory, where measurements were made on a material structure that concurrently has superconductivity and the quantum Hall effect.

Cornell University scientists have identified a new contender when it comes to quantum materials for computing and low-temperature electronics.

Using nitride-based materials, the researchers created a material structure that simultaneously exhibits superconductivity — in which electrical resistance vanishes completely — and the quantum Hall effect, which produces resistance with extreme precision when a magnetic field is applied.

“This is a beautiful marriage of the two things we know, at the microscale, that give electrons the most startling quantum proper...

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Graphite Offers up New Quantum Surprise

Graphite films

Dimensional reduction, quantum Hall effect and layer parity in graphite filmsNature Physics, 2019; DOI: 10.1038/s41567-019-0427-6

Researchers observe an unusual quantum Hall effect in the old 3D material. Researchers at The University of Manchester in the UK, led by Dr Artem Mishchenko, Prof Volodya Fal’ko and Prof Andre Geim, have discovered the quantum Hall effect in bulk graphite – a layered crystal consisting of stacked graphene layers. This is an unexpected result because the quantum Hall effect is possible only in so-called 2D systems where electrons’ motion is restricted to a plane and must be disallowed in the perpendicular direction...

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Mechanism for Generating Electric Current Without Energy Consumption at Room Temperature identified

Understanding the mechanism for generating electric current without energy consumption at room temperature

Ferromagnetism mediated by Sb or Te atoms. Credit: Hiroshima University

A group of researchers in Japan and China identified the requirements for the development of new types of extremely low power consumption electric devices by studying Cr-doped (Sb, Bi)2Te3 thin films.

At extremely low temperatures, an electric 3current flows around the edge of the film without energy loss, and under no external magnetic field. This attractive phenomenon is due to the material’s ferromagnetic properties. For the first time, researchers have revealed the mechanism by which this occurs. “Hopefully, this achievement will lead to the creation of novel materials that operate at room temperature in the future,” said Prof Akio Kimura.

Their achievement can be traced back to the discovery of the quantum Hall ef...

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