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تسجيل مستخدم جديدCrossover between the Dense Electron-Hole Phase and the BCS Excitonic Phase in Quantum Dots
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Boris A. Rodriguez
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Second order perturbation theory and a Lipkin-Nogami scheme combined with an exact Monte Carlo projection after variation are applied to compute the ground-state energy of $6le Nle 210$ electron-hole pairs confined in a parabolic two-dimensional quantum dot. The energy shows nice scaling properties as N or the confinement strength is varied. A crossover from the high-density electron-hole phase to the BCS excitonic phase is found at a density which is roughly four times the close-packing density of excitons.
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