Behaviour of an optically trapped probe approaching a dielectric interface

0205624 - UPT-D 20030006 RIV GB eng J - Journal Article
Jákl, Petr - Šerý, Mojmír - Ježek, Jan - Jonáš, Alexandr - Liška, M. - Zemánek, Pavel
Behaviour of an optically trapped probe approaching a dielectric interface.
Journal of Modern Optics. Roč. 50, č. 10 (2003), s. 1615 - 1625. ISSN 0950-0340. E-ISSN 1362-3044
R&D Projects: GA ČR GA101/00/0974
Institutional research plan: CEZ:AV0Z2065902
Keywords : trapping beam * optically trapped probe * standing-wave
Subject RIV: BH - Optics, Masers, Lasers
Impact factor: 1.213, year: 2003

The way in which reflection of the trapping beam from a dielectric interface influences the distance of the trapped sphere from the beam waist is studied theoretically and experimentally. The reflected wave interferes with the incident wave and they create a standing-wave component in the total axial intensity distribution. This component then modulates the trapping potential and creates several possible equilibrium positions for the trapped sphere. When the beam waist approaches the surface, the potential profile changes, which consequently causes jumps of the trapped probe from its current location to a deeper potential well. We suggested theoretically and proved experimentally that the magnitude of these unwanted jumps between the neighbouring equilibrium positions can be decreased by a suitable size of the sphere.
Permanent Link: http://hdl.handle.net/11104/0101237