Charge and spin textures of Ising quantum Hall ferromagnet domain walls

TY - JOUR

T1 - Charge and spin textures of Ising quantum Hall ferromagnet domain walls

AU - Danon, Jeroen

AU - Balram, Ajit C.

AU - Sanchez, Samuel

AU - Rudner, Mark S.

N1 - [Qdev]

PY - 2019/12/5

Y1 - 2019/12/5

N2 - We investigate the charge and spin structures associated with arbitrary smooth polarization textures in Ising (integer) quantum Hall ferromagnets. We consider the case where the two polarizations (denoted "pseudospin" up and down) correspond to states with opposite physical spin and different Landau level indices, n↑ and m↓. We derive analytic expressions for the charge and spin densities, as functions of the underlying pseudospin texture, and use these results to investigate different types of linear domain walls, both analytically and numerically. We find that any smooth domain wall between two oppositely polarized domains carries a universal quantized charge dipole density proportional to the difference of Landau level indices, n-m. Additionally, nonuniformities in the domain wall may give rise to excess net charge localized at the domain wall. Interestingly, the physical spin density associated with the domain wall generally exhibits a much more complex multipolar structure than that of the pseudospin texture. These results should for example help to elucidate the mechanisms underlying nuclear electric resonance and nuclear polarization oscillations in Ising quantum Hall systems.

AB - We investigate the charge and spin structures associated with arbitrary smooth polarization textures in Ising (integer) quantum Hall ferromagnets. We consider the case where the two polarizations (denoted "pseudospin" up and down) correspond to states with opposite physical spin and different Landau level indices, n↑ and m↓. We derive analytic expressions for the charge and spin densities, as functions of the underlying pseudospin texture, and use these results to investigate different types of linear domain walls, both analytically and numerically. We find that any smooth domain wall between two oppositely polarized domains carries a universal quantized charge dipole density proportional to the difference of Landau level indices, n-m. Additionally, nonuniformities in the domain wall may give rise to excess net charge localized at the domain wall. Interestingly, the physical spin density associated with the domain wall generally exhibits a much more complex multipolar structure than that of the pseudospin texture. These results should for example help to elucidate the mechanisms underlying nuclear electric resonance and nuclear polarization oscillations in Ising quantum Hall systems.

U2 - 10.1103/PhysRevB.100.235406

DO - 10.1103/PhysRevB.100.235406

M3 - Journal article

SN - 2469-9950

VL - 100

JO - Physical Review B

JF - Physical Review B

IS - 23

M1 - 235406

ER -