近日，美国哈佛大学的Hongkun Park与瑞士苏黎世联邦理工学院的Eugene Demler等人合作并取得一项新进展。他们发现一种源自量子晶体-液体转变的电子微乳液相。相关研究成果已于2025年1月20日在国际知名学术期刊《自然—物理学》上发表。
该研究团队利用低温反射光谱和磁光光谱技术，在单层MoSe2中观察到了电子维格纳晶体与电子液体之间形成的微乳液相的特征。研究发现，进入这种微乳液相状态的转变伴随着激子反射率、自旋磁化率和倒逆散射的异常变化，从而确立了它作为电子物质的一种独特相态。
据悉，强相互作用的电子系统往往会展现出复杂的相图，这是由不同量子基态之间竞争所导致的。这些相图的一个特征是微乳液相的出现，其中不同相的区域在多个长度尺度上自组织排列。对这些微乳液相进行实验表征可能会带来相当大的挑战，因为长程库仑相互作用在微观上与相互竞争的态交织在一起。
附：英文原文
Title: An electronic microemulsion phase emerging from a quantum crystal-to-liquid transition
Author: Sung, Jiho, Wang, Jue, Esterlis, Ilya, Volkov, Pavel A., Scuri, Giovanni, Zhou, You, Brutschea, Elise, Taniguchi, Takashi, Watanabe, Kenji, Yang, Yubo, Morales, Miguel A., Zhang, Shiwei, Millis, Andrew J., Lukin, Mikhail D., Kim, Philip, Demler, Eugene, Park, Hongkun
Issue&Volume: 2025-01-20
Abstract: Strongly interacting electronic systems often exhibit a complicated phase diagram that results from the competition between different quantum ground states. One feature of these phase diagrams is the emergence of microemulsion phases, where regions of different phases self-organize across multiple length scales. The experimental characterization of these microemulsions can pose considerable challenges, as the long-range Coulomb interaction microscopically mingles with the competing states. Here we observe the signatures of the microemulsion between an electronic Wigner crystal and an electron liquid in a MoSe2 monolayer using cryogenic reflectance and magneto-optical spectroscopy. We find that the transition into this microemulsion state is marked by anomalies in exciton reflectance, spin susceptibility and umklapp scattering, establishing it as a distinct phase of electronic matter.
DOI: 10.1038/s41567-024-02759-8
Source: https://www.nature.com/articles/s41567-024-02759-8