NMR Evidence for Spin-Pseudospin Intermixing in Quantum Hall Skyrmions

Norio Kumada; Koji Muraki

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arXiv · 0911.2553

NMR Evidence for Spin-Pseudospin Intermixing in Quantum Hall Skyrmions

Norio Kumada·Koji Muraki

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Abstract

We investigate quasiparticles in bilayer quantum Hall systems around total filling factor nu =1 by current-pumped and resistively detected NMR. The measured Knight shift reveals that the spin component in the quasiparticle increases continuously with $Δ_{SAS}$. Combined with results for the pseudospin component obtained by activation gap measurements, this demonstrates that both spin and pseudospin are contained in a quasiparticle at intermediate $Δ_{SAS}$, providing evidence for the existence of the spin-pseudospin intermixed SU(4) skyrmion. Nuclear spin relaxation measurements show that the collective behavior of the SU(4) skyrmion system qualitatively changes with $Δ_{SAS}$.

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Norio Kumada, Koji Muraki. 2009-11-13. NMR Evidence for Spin-Pseudospin Intermixing in Quantum Hall Skyrmions. https://arxiv.org/abs/0911.2553

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