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Self Assembled II-VI Magnetic Quantum Dot as a Voltage-Controlled Spin-Filter

C. Gould·A. Slobodskyy·T. Slobodskyy·P. Grabs·D. Supp·P. Hawrylak·F. Qu·G. Schmidt·L. W. Molenkamp
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Abstract

A key element in the emergence of a full spintronics technology is the development of voltage controlled spin filters to selectively inject carriers of desired spin into semiconductors. We previously demonstrated a prototype of such a device using a II-VI dilute-magnetic semiconductor quantum well which, however, still required an external magnetic field to generate the level splitting. Recent theory suggests that spin selection may be achievable in II-VI paramagnetic semiconductors without external magnetic field through local carrier mediated ferromagnetic interactions. We present the first experimental observation of such an effect using non-magnetic CdSe self-assembled quantum dots in a paramagnetic (Zn,Be,Mn)Se barrier.

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C. Gould, A. Slobodskyy, T. Slobodskyy, P. Grabs, D. Supp, P. Hawrylak, F. Qu, G. Schmidt, L. W. Molenkamp. 2005-01-25. Self Assembled II-VI Magnetic Quantum Dot as a Voltage-Controlled Spin-Filter. https://doi.org/10.1103/physrevlett.97.017202

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