Sagnac interferometer-enhanced particle tracking in optical tweezers

dc.contributor.authorTaylor, Michael A
dc.contributor.authorKnittel, Joachim
dc.contributor.authorHsu, Magnus
dc.contributor.authorBachor, Hans
dc.contributor.authorBowen, Warwick
dc.description.abstractA set-up is proposed to enhance tracking of very small particles, by using optical tweezers embedded within a Sagnac interferometer. The achievable signal-to-noise ratio is shown to be enhanced over that for standard back-focal-plane interferometry. The enhancement factor increases asymptotically as the interferometer visibility approaches 100%, but is capped at a maximum given by four times the ratio of the trapping field intensity to the detector saturation threshold. For an achievable visibility of 95%, the signal-to-noise ratio can be enhanced by a factor of up to 158 and the minimum trackable particle size is 2.3 times smaller than without the interferometer. This technique is particularly useful for optical tweezers which require counter-propagating trap beams.
dc.publisherInstitute of Physics Publishing
dc.sourceJournal of Optics
dc.subjectKeywords: Back focal planes; Counterpropagating; Enhancement factor; particle tracking; Sagnac interferometer; Signal to noise; Small particles; Trapping fields; Fiber optic sensors; Interferometers; Shot noise; Signal to noise ratio; Visibility; Optical tweezers optical tweezers; particle tracking; Sagnac interferometer; shot noise limited sensing
dc.titleSagnac interferometer-enhanced particle tracking in optical tweezers
dc.typeJournal article
local.contributor.affiliationTaylor, Michael A, University of Queensland
local.contributor.affiliationKnittel, Joachim, University of Queensland
local.contributor.affiliationHsu, Magnus, University of Queensland
local.contributor.affiliationBachor, Hans, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationBowen, Warwick, University of Queensland
local.contributor.authoruidBachor, Hans, u8203655
local.description.notesImported from ARIES
local.identifier.absfor020502 - Lasers and Quantum Electronics
local.identifier.absseo970102 - Expanding Knowledge in the Physical Sciences
local.type.statusPublished Version