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Optical Trapping in Air of an Individual Nanotube-Sphere Device



Andrew J. Slifka, Gurpreet Singh, Paul Rice, Damian S. Lauria, Roop Mahajan


We demonstrate the optical manipulation of a polystyrene bead in air attached to an individual carbon nanotube. In continuation of our previous work [1] we have also utilized this technique to demonstrate the calibration of a nanotube-sphere (NT-sphere) mechanical force sensor in the pN force range. The bead was trapped using a focused 1.064 μm IR laser operated at 100 mW power. The device fabrication was carried out using a micromanipulator inside a scanning electron microscope. This simple device acts as a micro-cantilever beam and consists of a tungsten probe with a long nanotube (length l ≥15 μm) attached to its tip, while the other end of the nanotube supports a polystyrene microsphere. Decreasing the nanotube length to 8 μm did not show any sphere motion in the trap, indicating that this force sensor calibration technique will only work for a very low range of forces (pN or fN).
Optics Letters


force calibration, nanotube, optical trap, piconewton force


Slifka, A. , Singh, G. , Rice, P. , Lauria, D. and Mahajan, R. (2012), Optical Trapping in Air of an Individual Nanotube-Sphere Device, Optics Letters, [online], (Accessed April 14, 2024)
Created August 10, 2012, Updated November 10, 2018