Singh Krishna Kant, Kumar Deepak, Singh Ajitesh, Goswami Debabrata
Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India.
Centre of Lasers and Photonics, Indian Institute of Technology Kanpur, Kanpur 208016, India.
J Phys Chem Lett. 2024 Oct 17;15(41):10360-10365. doi: 10.1021/acs.jpclett.4c01889. Epub 2024 Oct 7.
Optical tweezers use strongly focused light for trapping, characterizing, and manipulating objects in the microscopic and nanoscopic regimes. However, fully understanding optical trapping at the nanoscale remains a significant challenge. This holds importance because the nanoscale is the frontier for numerous promising advancements, ranging from enhancing single-molecule investigations in biology to developing hybrid devices for nanoelectronics and photonics and exploring fundamental quantum phenomena in opto-mechanics. We report an experimental and theoretical study of nanoparticles of various sizes, showing the advantages of the immense peak power of ultrashort laser pulses over conventional optical tweezers. We also demonstrate highly stable trapping of nanoparticles for extended durations at low average laser power using femtosecond lasers.
光镊利用强聚焦光在微观和纳米尺度下捕获、表征和操纵物体。然而，全面理解纳米尺度下的光捕获仍然是一项重大挑战。这一点很重要，因为纳米尺度是众多有前景进展的前沿领域，从增强生物学中的单分子研究到开发用于纳米电子学和光子学的混合器件，以及探索光机械学中的基本量子现象。我们报告了对各种尺寸纳米颗粒的实验和理论研究，展示了超短激光脉冲的巨大峰值功率相对于传统光镊的优势。我们还展示了使用飞秒激光在低平均激光功率下对纳米颗粒进行长时间的高度稳定捕获。
