Enhancement of the Raman spectrum of optically levitated microspheres by seeded nanoparticles

Abstract

Optical levitation experiments were performed with diethyl sebacate and diethyl hexylsebacate particles with a diameter range of 20–30 μm. The particles were seeded with polystyrene–latex particles with a diameter of 90 nm. Elastically and inelastically scattered light was recorded simultaneously. Although no change in the Mie scattering could be observed, the nonresonant part of the Raman spectrum was raised by a factor of 2. The C–H stretching region between 2800 and 3100 cm−1 was investigated, and the time dependence of the Raman intensity was measured at a fixed wave number of Δν = 2920 cm−1.