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Exchange interaction effects in the thermodynamic properties of quantum dots

Luis G. Dias da Silva·Nelson Studart
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Abstract

We study electron-electron interaction effects in the thermodynamic properties of quantum-dot systems. We obtain the direct and exchange contributions to the specific heat C_v in the self-consistent Hartree-Fock approximation at finite temperatures. An exchange-induced phase transition is observed and the transition temperature is shown to be inversely proportional to the size of the system. The exchange contribution to C_v dominates over the direct and kinetic contributions in the intermediate regime of interaction strength (r_s ~ 1). Furthermore, the electron-electron interaction modifies both the amplitude and the period of magnetic field induced oscillations in C_v.

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Luis G. Dias da Silva, Nelson Studart. 2004-12-20. Exchange interaction effects in the thermodynamic properties of quantum dots. https://doi.org/10.1103/physrevb.71.113302

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