Hester Brooke, Campbell Gretchen K, López-Mariscal Carlos, Filgueira Carly Levin, Huschka Ryan, Halas Naomi J, Helmerson Kristian
Physics and Astronomy Department, Appalachian State University, 525 Rivers Street, Boone, North Carolina 28608, USA.
Rev Sci Instrum. 2012 Apr;83(4):043114. doi: 10.1063/1.4704373.
Optical trapping forces depend on the difference between the trap wavelength and the extinction resonances of trapped particles. This leads to a wavelength-dependent trapping force, which should allow for the optimization of optical tweezers systems, simply by choosing the best trapping wavelength for a given application. Here we present an optical tweezer system with wavelength tunability, for the study of resonance effects. With this system, the optical trap stiffness is measured for single trapped particles that exhibit either single or multiple extinction resonances. We include discussions of wavelength-dependent effects, such as changes in temperature, and how to measure them.
光阱力取决于阱波长与被捕获粒子的消光共振之间的差异。这导致了一种与波长相关的捕获力，通过为给定应用选择最佳捕获波长，应可实现光镊系统的优化。在此，我们展示了一种具有波长可调性的光镊系统，用于研究共振效应。利用该系统，对表现出单重或多重消光共振的单个被捕获粒子测量了光阱刚度。我们还讨论了与波长相关的效应，如温度变化以及如何测量这些效应。
