A revolution in optical manipulation

Abstract

Optical tweezers use the forces exerted by a strongly focused beam of light to trap and move objects ranging in size from tens of nanometres to tens of micrometres. Since their introduction in 1986, the optical tweezer has become an important tool for research in the fields of biology, physical chemistry and soft condensed matter physics. Recent advances promise to take optical tweezers out of the laboratory and into the mainstream of manufacturing and diagnostics; they may even become consumer products. The next generation of single-beam optical traps offers revolutionary new opportunities for fundamental and applied research.

An optical toolbox for total control of droplet microfluidics

“…Our approach to controlling microfluidic droplets relies on all-optical techniques which have been greatly developed in recent years in connection with microfluidic devices [21,22,23,24,25]. Indeed, optical trapping has become a standard tool in biophysics [26] and holographic [22] and generalized phase contrast [25] methods now allow a single laser to be divided into many spots which can be independently manipulated.…”

Continuous particle separation based on electrical properties using alternating current dielectrophoresis

“…To achieve these, various techniques have been developed to be used in microsystems such as optical tweezers [1], magnetophoresis [2], acoustic means [3,4,5] and dielectrophoresis (DEP). Among these, DEP is one of the most popular methods for particle manipulation in microsystems due to (i) its favorable scaling effects [6], (ii) the simplicity of the instrumentation and (iii) its ability to induce both negative and positive forces [7].…”

Optical trapping and binding of particles in an optofluidic stable Fabry–Pérot resonator with single-sided injection

“…1 To this end, the majority ofexperimental setups adopt free space tightly focused light 20 beams to achieve the gradient in the electromagnetic field needed for obtaining optical tweezers; but most often than not, the optical setup is off-chip and requires rather high optical power, typically hundreds of milliwatts or even few watts. [1][2][3][4] To overcome the bulky, free space universaloptical tweezers, 25 the use of optical integrated structures and optical resonators is being extensively investigatedto achieve on-chip, low power and compact size optical traps; which led to the development of different configurations to achieve localization control and/or simple manipulation. To name some of these on-chip optical 30 trapping modules: evanescent fields from waveguides and Whispering Gallery Mode resonators,in the form of ring resonators, 5 disks, 6 or spheres 7 are used to propel particles along the light propagating path.Multimode-interference (MMI) structures 8 and photonic crystals 9 are used to trap particles at 35 specific locations.…”