title: Raman, hyper-Raman, hyper-Rayleigh, two-photon luminescence and morphology-dependent resonance modes in a single optical tweezers system.
abstract: We present a setup of optical tweezers combined with linear and nonlinear microspectroscopies that enhances the capabilities of capture and analysis of both techniques. We can use either a continuous-wave (cw) Ti:sapphire laser for Raman measurements or a pulsed femtosecond Ti:sapphire laser that permitted the observation of nonlinear results such as hyper-Raman, hyper-Rayleigh, and two-photon luminescence. Only the high peak intensity of the femtosecond laser allows the observation of all these nonlinear spectroscopies. The sensitivity of our system also permitted the observation of morphology-dependent resonance (MDR) modes of a single stained trapped microsphere of 6 microm. The possibility of performing spectroscopy in a living microorganism optically trapped in any desired neighborhood would mean that one can dynamically observe the chemical reactions and/or mechanical properties changing in real time.
authors.affiliation: Instituto de Física Gleb Wataghin UNICAMP, Campinas-SP, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Fontes
authors.forename: K
authors.initials: K
authors.lastname: Ajito
authors.forename: A A R
authors.initials: AA
authors.lastname: Neves
authors.forename: W L
authors.initials: WL
authors.lastname: Moreira
authors.forename: A A
authors.initials: AA
authors.lastname: de Thomaz
authors.forename: L C
authors.initials: LC
authors.lastname: Barbosa
authors.forename: A M
authors.initials: AM
authors.lastname: de Paula
authors.forename: C L
authors.initials: CL
authors.lastname: Cesar