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تسجيل مستخدم جديدDensity dependence of valley polarization energy for composite fermions
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In two-dimensional electron systems confined to wide AlAs quantum wells, composite fermions around the filling factor $ u$ = 3/2 are fully spin polarized but possess a valley degree of freedom. Here we measure the energy needed to completely valley polarize these composite fermions as a function of electron density. Comparing our results to the existing theory, we find overall good quantitative agreement, but there is an unexpected trend: The measured composite fermion valley polarization energy, normalized to the Coulomb energy, decreases with decreasing density.
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