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تسجيل مستخدم جديدThermodynamic Evidence for Nanoscale Bose-Einstein Condensation in ^4He Confined in Nanoporous Media
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We report the measurements of the heat capacity of ^4He confined in nanoporous Gelsil glass that has nanopores of 2.5-nm diameter at pressures up to 5.3 MPa. The heat capacity has a broad peak at a temperature much higher than the superfluid transition temperature obtained using the torsional oscillator technique. The peak provides a definite thermodynamic evidence for the formation of localized Bose-Einstein condensates (LBECs) on nanometer length scales. The temperature dependence of heat capacity is well described by the excitations of phonons and rotons, supporting the existence of LBEC.
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We have studied the liquid - solid (L-S) phase transition of ^4He confined in nanoporous glass, which has interconnected nanopores of 2.5 nm in diameter. The L-S boundary is determined by the measurements of pressure and thermal response during slow
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The superfluid transition in liquid 4He filled in Gelsil glass observed in recent experiments is discussed in the framework of quantum critical phenomena. We show that quantum fluctuations of phase are indeed important at the experimentally studied t
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