The possibility of an intrinsic spin lattice in high-mobility semiconductor heterostructures

Siegert, Christoph and Ghosh, Arindam and Pepper, Michael and Farrer, Ian and Ritchie, David A (2007) The possibility of an intrinsic spin lattice in high-mobility semiconductor heterostructures. In: Nature Physics, 3 (5). pp. 315-318.

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Abstract

Embedding magnetic moments into semiconductor heterostructures offers a tuneable access to various forms of magnetic ordering and phase transitions in low- dimensional electron systems. In general, the moments are introduced artificially, by either doping with ferromagnetic atoms, or electrostatically confining odd-electron quantum $dots ^{1-4}$. Here, we report experimental evidence of an independent, and intrinsic, source of localized spins in high-mobility GaAs/AlGaAs heterostructures with large setback distance $(\approx80 nm)$ in modulation doping. Measurements reveal a quasi-regular distribution of the spins in the delocalized Fermi sea, and a mutual interaction via the Ruderman–Kittel–Kasuya–Yosida (RKKY) indirect exchange below 100 mK.We show that a simple model on the basis of the fluctuations in background potential on the host two-dimensional electron system can explain the observed results quantitatively, which suggests a ‘disordertemplated’ microscopic origin of the localized moments.

Item Type:	Journal Article
Publication:	Nature Physics
Publisher:	Nature Publishing Group
Additional Information:	Copyright of this aticle belongs to Nature Publishing Group.
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	27 Aug 2007
Last Modified:	19 Sep 2010 04:39
URI:	http://eprints.iisc.ac.in/id/eprint/11733

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