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Unique Spin Vortices and Topological Charges in Quantum Dots with Spin-orbit Couplings.

ABSTRACT: Spin textures of one or two electrons in a quantum dot with Rashba or Dresselhaus spin-orbit couplings reveal several intriguing properties. We show here that even at the single-electron level stable spin vortices with tunable topological charges exist. These topological textures appear in the ground state of the dots. The textures are stabilized by time-reversal symmetry breaking and are robust against the eccentricity of the dot. The topological charge is directly related to the sign of the z component of the spin in a large dot, allowing a direct probe of its topological properties. This would clearly pave the way to possible future topological spintronics. The phenomenon of spin vortices persists for the interacting two-electron dot in the presence of a magnetic field.

SUBMITTER: Luo W

PROVIDER: S-EPMC6345826 | biostudies-other | 2019 Jan

REPOSITORIES: biostudies-other

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Unique Spin Vortices and Topological Charges in Quantum Dots with Spin-orbit Couplings.

Luo Wenchen W Naseri Amin A Sirker Jesko J Chakraborty Tapash T

Scientific reports 20190124 1

Spin textures of one or two electrons in a quantum dot with Rashba or Dresselhaus spin-orbit couplings reveal several intriguing properties. We show here that even at the single-electron level stable spin vortices with tunable topological charges exist. These topological textures appear in the ground state of the dots. The textures are stabilized by time-reversal symmetry breaking and are robust against the eccentricity of the dot. The topological charge is directly related to the sign of the z ...[more]

PMID: 30679442

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