2026-04-13T01:38:12Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/533232025-12-05T14:47:33Zcom_2072_1057col_2072_478821col_2072_478917

00925njm 22002777a 4500 dc Marsà, Ferran author Farré Flaquer, Arnau author Martín Badosa, Estela author Montes Usategui, Mario author 2014-04-08T06:56:09Z 2014-04-08T06:56:09Z 2013-12-16 2014-04-08T06:56:10Z A major problem with holographic optical tweezers (HOTs) is their incompatibility with laser-based position detection methods, such as back-focal-plane interferometry (BFPI). The alternatives generally used with HOTs, like high-speed video tracking, do not offer the same spatial and temporal bandwidths. This has limited the use of this technique in precise quantitative experiments. In this paper, we present an optical trap design that combines digital holography and back-focal-plane displacement detection. We show that, with a particularly simple setup, it is possible to generate a set of multiple holographic traps and an additional static non-holographic trap with orthogonal polarizations and that they can be, therefore, easily separated for measuring positions and forces with the high positional and temporal resolutions of laser-based detection. We prove that measurements from both polarizations contain less than 1% crosstalk and that traps in our setup are harmonic within the typical range. We further tested the instrument in a DNA stretching experiment and we discuss an interesting property of this configuration: the small drift of the differential signal between traps. Nanotecnologia Holografia ADN Aparells i instruments científics Biofísica Nanotechnology Holography DNA Scientific apparatus and instruments Biophysics Holographic optical tweezers combined with back-focal-plane displacement detection