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arXiv · 0812.4890

Cyclotron spin-flip excitations in a \nu=1/3 quantum Hall ferromagnet

A. B. Van'kov·L. V. Kulik·S. M. Dickmann·I. V. Kukushkin·V. E. Kirpichev·W. Dietsche·S. Schmult
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Abstract

Inelastic light scattering spectroscopy around the \nu=1/3 filling discloses a novel type of cyclotron spin-flip excitation in a quantum Hall system in addition to the excitations previously studied. The excitation energy of the observed mode follows qualitatively the degree of electron spin polarization, reaching a maximum value at \nu=1/3 and thus characterizing it as a \nu=1/3 ferromagnet eigenmode. Its absolute energy substantially exceeds the theoretical prediction obtained within the renowned single-mode approximation. Double-exciton corrections neglected utilizing the single-mode approach are evaluated within the framework of the excitonic representation and are inferred to be responsible for the observed effect.

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A. B. Van'kov, L. V. Kulik, S. M. Dickmann, I. V. Kukushkin, V. E. Kirpichev, W. Dietsche, S. Schmult. 2008-12-29. Cyclotron spin-flip excitations in a \nu=1/3 quantum Hall ferromagnet. https://doi.org/10.1103/physrevlett.102.206802

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