The present review summarizes the recent studies on the thermodynamic properties of pairing in many-body systems including superconductors, metallic nanosized clusters and/or grains, solid-state materials, focusing on the excited nuclei, that is nuclei at finite temperature and/or angular momentum formed via heavy-ion fusion, [Formula: see text]-induced fusion reactions, or inelastic scattering of light particles on heavy targets. Because of the finiteness of the systems, several interesting effects of pairing such as nonvanishing pairing gap, smoothing of superfluid-normal phase transition, first and second order phase transitions, pairing reentrance, etc, will be discussed in detail. Influences of exact and approximate thermal pairing on some nuclear properties such as temperature-dependent width of the giant dipole resonance, total level density, and radiative strength function of the [Formula: see text]-rays emission will be also analyzed. Finally, the first experimental evidence of the pairing reentrance phenomenon in a 104Pd nucleus as well as its solid-state counterpart of ferromagnets under strong magnetic field will be presented.

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激发核配对：综述

本综述总结了最近关于多体系统配对热力学性质的研究，包括超导体、金属纳米簇和/或晶粒、固态材料，重点是受激核，即有限温度和/或角的核。通过重离子聚变形成的动量，[公式：见正文]诱导的聚变反应，或轻粒子在重目标上的非弹性散射。由于系统的有限性，将详细讨论配对的几个有趣的影响，例如非零配对间隙、超流体-法向相变的平滑、一阶和二阶相变、配对重入等。精确和近似热配对对一些核特性的影响，例如巨偶极共振的温度相关宽度，还将分析[公式：见正文]-射线发射的总能级密度和辐射强度函数。最后，将展示强磁场下 104Pd 核及其固态铁磁体配对重入现象的第一个实验证据。