Interdisciplinary Materials Science, Vanderbilt University, Nashville, Tennessee 37235, USA.
Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University, Nashville, Tennessee 37235, USA.
Phys Rev Lett. 2023 Feb 24;130(8):083802. doi: 10.1103/PhysRevLett.130.083802.
Photonic crystal cavities with bowtie defects that combine ultrahigh Q and ultralow mode volume are theoretically studied for low-power nanoscale optical trapping. By harnessing the localized heating of the water layer near the bowtie region, combined with an applied alternating current electric field, this system provides long-range electrohydrodynamic transport of particles with average radial velocities of 30 μm/s towards the bowtie region on demand by switching the input wavelength. Once transported to a given bowtie region, synergistic interaction of optical gradient and attractive negative thermophoretic forces stably trap a 10 nm quantum dot in a potential well with a depth of 10 k_{B}T using a mW input power.
理论上研究了具有蝶形缺陷的光子晶体腔，其具有超高 Q 值和超低模式体积，可用于低功率纳米光学捕获。通过利用蝶形区域附近水层的局部加热，结合外加交流电场，该系统通过切换输入波长按需实现对粒子的长程电动力学输运，平均径向速度可达 30 μm/s。一旦被输送到给定的蝶形区域，光梯度和吸引力负热泳力的协同作用可以使用 1 mW 的输入功率，在 10 kBT 的深度下稳定地捕获 10nm 的量子点。
