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تسجيل مستخدم جديدEvidence of a first order phase transition between Wigner crystal and Bubble Phases of 2D electrons in higher Landau levels
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For filling factors $ u$ in the range between 4.16 and 4.28, we simultaneously detect {it two} resonances in the real diagonal microwave conductivity of a two--dimensional electron system (2DES) at low temperature $T approx 35$ mK. We attribute the resonances to Wigner crystal and Bubble phases of the 2DES in higher Landau Levels. For $ u$ below and above this range, only single resonances are observed. The coexistence of both phases is taken as evidence of a first order phase transition. We estimate the transition point as $ u=4.22$.
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We have measured the diagonal conductivity in the microwave regime of an ultrahigh mobility two dimensional electron system. We find a sharp resonance in Re[sigma_{xx}] versus frequency when nu > 4 and the partial filling of the highest Landau level,
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