Superconducting first-order pairing: Finite-temperature simulations†

摘要: A recently developed first-order mechanism for superconducting pairing has been extended from T = 0 K to finite temperatures. On the basis of quantum statistical considerations, we have suggested a direct interaction that does not necessarily involve second-order elements, such as electron–phonon coupling or specific magnetic interactions submitted by spin fluctuations. The driving force (energy-driven) is an attenuation destabilizing influence Pauli antisymmetry principle (PAP). Only moves unpaired fermions are controlled PAP, while Cooper pairs not. statistics mixed type, it combines fermionic on-site and bosonic intersite properties. strong correlation between strength PAP constraints system topology in combination with electron number discussed some larger clusters. Detailed finite-temperature simulations on performed four-center–four-electron clusters different topologies. canonical ensemble employed derive electronic energy, configuration entropy, free energy paired states thermal equilibrium. show can be caused either entropy. coexistence two sets particles (i.e., electrons) lead enhanced In this context, discuss possibility entropy-driven high-temperature superconductor emerging low-temperature state. charge degrees freedom systems studied help fluctuations helpful judging validity theories based interactions. measure carrier delocalization states. well-known proximity Jahn–Teller activity superconductivity analyzed zero-temperature limit. It demonstrated both processes compete their ability reduce constraints. All theoretical results derived within framework simple Hubbard Hamiltonian. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005