量子系统在热环境中的耗散和退相是光谱学研究中的重要课题之一。一般来说，耗散会导致光谱线形的展宽，因此更强的系统-环境相互作用可能会使得二维电子光谱出现更为显著的均匀展宽，对光谱结果的解释和应用产生不利影响。然而，本文揭示了一个与此相反的异常现象：在电磁诱导透明的作用下，由于细致平衡条件的存在，较高温度下二维电子光谱的均匀展宽可以显著减小。这种异常效应是由于二维电子光谱中持续存在的非对角峰引起的。

本文的创新点和关键结论包括：

（1）本文发现了在高温条件下二维电子光谱的均匀展宽异常降低的现象，这一结果归因于电磁诱导透明效应辅助下的细致平衡条件。研究采用了四能级模型，观察到在两个激发态能级近共振的情况下，相较于低温，高温下光谱的均匀展宽反而更窄，谱线分辨率更高。接着，通过进一步研究大失谐情况揭示了这一反常现象的原因，即由于持续时间较长的非对角峰值导致的。在低温下，非对角峰会消失，而高温下则持续存在。这些发现不仅揭示了高温条件下二维电子光谱的特殊性质，还为理解这一性质背后的物理机制提供了重要线索。

（2）在许多复杂系统中，能级的静态无序是一种不可避免且普遍存在的现象，会对光谱的形态和特征产生重要影响。然而，我们的研究指出，即使考虑到能级的静态无序，只要能级分布的标准差在一定范围内，均匀展宽仍然会受到反常抑制，即（1）中的结论仍然成立。

（3）在相位重聚方向上，受激发射 2 项与基态漂白 3 项在实际实验中的分离具有一定的挑战性。因此，本文将研究范围进一步扩展到考虑 3 情况，以便更加全面地了解光谱的变化。在扩展研究中，我们发现当同时考虑到受激发射项和基态漂白项时，仍然可以观察到高温下均匀展宽受到抑制的现象，也就是说，细致平衡条件的影响仍然显著。通过对整个相位重聚方向上光谱的全面模拟，进一步强化了我们的研究，并且为将其应用到实验中提供了重要的参考依据。

The dissipation and decoherence of quantum systems in thermal environments are crucial topics in spectroscopic studies. It is generally believed that dissipation tends to broaden the line shape of spectroscopies and thus stronger system-bath interactions can result in more significant homogeneous broadening of two-dimensional electronic spectroscopy, adversely affecting the interpretation and application of spectroscopic results. However, here we show that the case can be the opposite in the regime of electromagnetically induced transparency. We predict that assisted by the electromagnetically induced transparency, the homogeneous broadening of the two-dimensional electronic spectroscopy at a higher temperature can be significantly reduced due to the detailed balance. This anomalous effect arises from the long-lasting off-diagonal peaks in two-dimensional electronic spectroscopy.

The key innovations and conclusions of this paper include:

(1) This study identifies, for the first time, the phenomenon of reduced homogeneous broadening in two-dimensional electronic spectroscopy at a higher temperature, attributed to the assistance of electromagnetically induced transparency in the presence of detailed balance. Utilizing a four-level model, it is observed that under condition of near-resonance between two higher energy levels, the spectroscopy at a higher temperature exhibits narrower homogeneous broadening compared to lower temperatures, accompanied by higher spectral resolution. Subsequent investigation into highly detuned scenarios reveals that this anomaly is caused by the prolonged presence of offdiagonal peaks. While these peaks disappear at low temperatures, they persist at high temperatures. These findings not only unveil the unique properties of two-dimensional electronic spectroscopy at elevated temperatures but also provide crucial clues for understanding the underlying physical mechanisms.

(2) In many complex systems, the static disorder of energy levels is an unavoidable and prevalent phenomenon that influences the morphology and characteristics of spectroscopy. However, our research indicates that even considering the existence of static disorder in energy levels, as long as the standard deviation of level fluctuations falls within a certain range, homogeneous broadening will still be anomalously suppressed, affirming the validity of our main conclusion in (1).

(3) In the rephasing direction, separating the stimulated emission 2 term from the ground-state bleaching 3 term poses certain challenges. Therefore, this paper further extends the scope of the study to consider the 3 scenario for a more comprehensive understanding of spectral variations. In the expanded investigation, it is discovered that even when considering both stimulated emission and ground-state bleaching terms simultaneously, the phenomenon of suppressed homogeneous broadening at high temperatures persists, indicating the continued significant influence of detailed balance. Through comprehensive simulations of spectroscopy in the entire rephasing direction, our study is further strengthened, providing valuable reference for its application in experiments.