Formation of spin droplet at nu=5/2 in an asymmetric quantum dot under quantum Hall conditions


Atci H., Siddiki A.

PHYSICAL REVIEW B, vol.95, no.4, 2017 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 95 Issue: 4
  • Publication Date: 2017
  • Doi Number: 10.1103/physrevb.95.045132
  • Journal Name: PHYSICAL REVIEW B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Istanbul University Affiliated: No

Abstract

In this work, a quantum dot that is defined asymmetrically by electrostatic means induced on a GaAs/AlGaAs heterostructure is investigated to unravel the effect of geometric constraints on the formation of spin droplets under quantized Hall conditions. The incompressibility of the excited nu = 5/2 state is explored by solving the Schr "odinger equation within spin density functional theory, where the confinement potential is obtained self-consistently utilizing the Thomas-Fermi approximation. Our numerical investigations show that the spatial distribution of the nu = 2 incompressible strips and electron occupation in the second lowest Landau level considerably differ from the results of the laterally symmetric quantum dots. Our findings yield two important consequences: first, the incompressibility of the intriguing nu= 5/2 state is strongly affected by the asymmetry, and second, since the Aharonov-Bohm interference patterns depend on the velocity of the particles, asymmetry yields an additional parameter to adjust the oscillation period, which imposes a boundary condition dependency in observing quasiparticle phases.