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Tuning of the Gap in a Laughlin-Bychkov-Rashba Incompressible Liquid

Marco Califano·Tapash Chakraborty·and Pekka Pietiläinen
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Abstract

We report on our investigation of the influence of Bychkov-Rashba spin-orbit interaction (SOI) on the incompressible Laughlin state. We find that experimentally obtainable values of the spin-orbit coupling strength can induce as much as a 25% increase in the quasiparticle-quasihole gap Eg at low magnetic fields in InAs, thereby increasing the stability of the liquid state. The SOI-modulated enhancement of Eg is also significant for filling factors 1/5 and 1/7, where the FQH state is usually weak. This raises the intriguing possibility of tuning, via the SO coupling strength, the liquid to solid transition to much lower densities.

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Marco Califano, Tapash Chakraborty, and Pekka Pietiläinen. 2004-11-19. Tuning of the Gap in a Laughlin-Bychkov-Rashba Incompressible Liquid. https://doi.org/10.1103/physrevlett.94.246801

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