从约化BCS哈密顿量推导零温BCS泛函的简单方法
A simple derivation of the zero-temperature BCS functional from the reduced BCS Hamiltonian
- Ludwig-Maximilians-Universität München（慕尼黑大学）
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中文总结 AI 辅助
该研究从约化BCS哈密顿量出发，推导得出零温BCS泛函，证明有限体积下精确基态能量与BCS泛函最小值的误差与体积无关，进而确立热力学极限下BCS变分原理对基态能量密度的精确性。
中文摘要 AI 辅助
我们在全费米子福克空间上考虑巨正则约化BCS哈密顿量，其吸引配对相互作用支撑在费米面附近的一个能壳中。对于固定化学势，我们证明有限体积的精确基态能量与对应有限体积BCS泛函的最小值之差为与体积无关的误差项，由此可得热力学极限下BCS变分原理对基态能量密度是精确的。
英文摘要
We consider a grand-canonical reduced BCS Hamiltonian on the full fermionic Fock space with an attractive pairing interaction supported in an energy shell around the Fermi surface. For fixed chemical potential, we prove that the exact finite-volume ground-state energy differs from the minimum of the corresponding finite-volume BCS functional by a volume-independent error. As a consequence, the BCS variational principle is exact for the ground-state energy density in the thermodynamic limit.
