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arXiv · 1003.1851

Bound Magnetic Polarons in the 3d-electron Ferromagnetic Spinel Semiconductor CdCr$_2$Se$_4$

Vyacheslav G. Storchak·Jess H. Brewer·Peter L. Russo·Scott L. Stubbs·Oleg E. Parfenov·Roger L. Lichti·Tel'man G. Aminov
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Abstract

Muon spin rotation/relaxation spectroscopy %(supported by magnetization measurements) has been employed to study electron localization around a donor center - the positive muon - in the 3d magnetic spinel semiconductor CdCr$_2$Se$_4$ at temperatures from 2 to 300 K in magnetic fields up to 7 T. A bound state of an electron around a positive muon - a magnetic polaron - is detected far above the ferromagnetic transition up to 300 K. Electron localization into a magnetic polaron occurs due to its strong exchange interaction with the magnetic 3d electrons of local Cr$^{3+}$ ions, which confines its wave function within R\approx 0.3 nm, allowing significant overlap with both the nearest and next nearest shells of Cr ions.

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Vyacheslav G. Storchak, Jess H. Brewer, Peter L. Russo, Scott L. Stubbs, Oleg E. Parfenov, Roger L. Lichti, Tel'man G. Aminov. 2010-03-09. Bound Magnetic Polarons in the 3d-electron Ferromagnetic Spinel Semiconductor CdCr$_2$Se$_4$. https://doi.org/10.1088/0953-8984%2F22%2F49%2F495601

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