| Autor: |
Wurstbauer, U., Levy, A. L., Pinczuk, A., West, K. W., Pfeiffer, L. N., Manfra, M. J., Gardner, G. C., Watson, J. D. |
| Rok vydání: |
2015 |
| Předmět: |
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| Zdroj: |
Phys. Rev. B 92, 241407 (2015) |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevB.92.241407 |
| Popis: |
We report the observation of low-lying collective charge and spin excitations in the second Landau level at {\nu} = 2 + 1/3 and also for the very fragile states at {\nu} = 2 + 2/5, 2 + 3/8 in inelastic light scattering experiments. These modes exhibit a clear dependence on filling factor and temperature substantiating the unique access to the characteristic neutral excitation spectra of the incompressible FQHE states. A detailed mode analysis reveals low energy modes at around 70 {\mu}eV and a sharp mode slightly below the Zeeman energy interpreted as gap and spin wave excitation, respectively. The lowest energy collective charge excitation spectrum at {\nu} = 2 + 1/3 exhibits significant similarities and a universal scaling of the energies with its cousin state in the lowest Landau level at {\nu} = 1/3 suggesting similar underlying physics. The observed excitation spectra facilitate to distinguish between theoretical descriptions of the nature of those FQHE states. A striking polarization dependence in light scattering is discussed in the framework of anisotropic electron phases that allow for the stabilization of nematic FQHE states. |
| Databáze: |
arXiv |
| Externí odkaz: |
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