近日，奥地利维也纳大学的Clemens Jakubec及其研究小组与智利康塞普西翁大学的Pablo Solano以及美国亚利桑那大学的 Kanu Sinha合作并取得一项新进展。经过不懈努力，他们对外场中纳米球上的涨落诱导力进行了研究。相关研究成果已于2024年5月7日在国际知名学术期刊《物理评论A》上发表。

该研究团队分析了在外部驱动存在的情况下，两个介电纳米球之间通过电磁场的量子涨落和热涨落介导的辐射力。研究人员将涨落力的散射理论描述推广到包括外部量子场，允许它们处于任意量子态。对外部相干态恢复了已知的捕获和光结合势。研究人员证明，尽管其平均强度为零，但外部压缩真空状态产生的电位与激光相似。此外，场的薛定谔态可以增强或抑制光势，这取决于它们是奇态还是偶态。

考虑到被光镊捕获的纳米球，研究人员研究了总粒子间势作为各种实验相关参数的函数，如场强度、极化和捕获激光的相位。他们证明一组合适的参数可以产生两个纳米球的相互束缚态，其电位深度可达约200K。这项研究结果与正在进行的宏观量子状态下捕获纳米球的实验有关，为宏观量子系统之间的工程相互作用铺平了道路。

附：英文原文

Title: Fluctuation-induced forces on nanospheres in external fields

Author: Clemens Jakubec, Pablo Solano, Uros Delic, Kanu Sinha

Issue&Volume: 2024/05/07

Abstract: We analyze the radiative forces between two dielectric nanospheres mediated via the quantum and thermal fluctuations of the electromagnetic field in the presence of an external drive. We generalize the scattering theory description of fluctuation forces to include external quantum fields, allowing them to be in an arbitrary quantum state. The known trapping and optical binding potentials are recovered for an external coherent state. We demonstrate that an external squeezed vacuum state creates similar potentials to a laser, despite its zero average intensity. Moreover, Schrdinger cat states of the field can enhance or suppress the optical potential depending on whether they are odd or even. Considering the nanospheres trapped by optical tweezers, we examine the total interparticle potential as a function of various experimentally relevant parameters, such as the field intensity, polarization, and phase of the trapping lasers. We demonstrate that an appropriate set of parameters could produce mutual bound states of the two nanospheres with potential depth as large as ～200K. Our results are pertinent to ongoing experiments with trapped nanospheres in the macroscopic quantum regime, paving the way for engineering interactions among macroscopic quantum systems.

DOI: 10.1103/PhysRevA.109.052807

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.052807