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The Collapse of the Spin-Singlet Phase in Quantum Dots

M. Ciorga·A. Wensauer·M. Pioro-Ladriere·M. Korkusinski·Jordan Kyriakidis·A. S. Sachrajda·P. Hawrylak
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Abstract

We present experimental and theoretical results on a new regime in quantum dots in which the filling factor 2 singlet state is replaced by new spin polarized phases. We make use of spin blockade spectroscopy to identify the transition to this new regime as a function of the number of electrons. The key experimental observation is a reversal of the phase in the systematic oscillation of the amplitude of Coulomb blockade peaks as the number of electrons is increased above a critical number. It is found theoretically that correlations are crucial to the existence of the new phases.

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M. Ciorga, A. Wensauer, M. Pioro-Ladriere, M. Korkusinski, Jordan Kyriakidis, A. S. Sachrajda, P. Hawrylak. 2002-03-28. The Collapse of the Spin-Singlet Phase in Quantum Dots. https://doi.org/10.1103/physrevlett.88.256804

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