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arXiv · 1301.6528

Stability of spin droplets in realistic quantum Hall devices

H. Atci·U. Erkarslan·A. Siddiki·E. Rasanen
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Abstract

We study the formation and characteristics of "spin droplets",i.e., compact spin-polarized configurations in the highest occupied Landau level, in an etched quantum Hall device at filling factors $2\leqν\leq3$. The confining potential for electrons is obtained with self-consistent electrostatic calculations on a GaAs/AlGaAs heterostructure with experimental system parameters. Real-space spin-density-functional calculations for electrons confined in the obtained potential show the appearance of stable spin droplets at $ν\sim 5/2$. The qualitative features of the spin droplet are similar to those in idealized (parabolic) quantum-dot systems. The universal stability of the state against geometric deformations underline the applicability of spin droplets in, e.g., spin-transport through quantum point contacts.

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H. Atci, U. Erkarslan, A. Siddiki, E. Rasanen. 2013-01-28. Stability of spin droplets in realistic quantum Hall devices. https://doi.org/10.1088/0953-8984%2F25%2F15%2F155604

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