Observation of a single-beam gradient force optical trap for dielectric particles
TL;DR: Optical trapping of dielectric particles by a single-beam gradient force trap was demonstrated for the first reported time, confirming the concept of negative light pressure due to the gradient force.
Abstract: Optical trapping of dielectric particles by a single-beam gradient force trap was demonstrated for the first reported time. This confirms the concept of negative light pressure due to the gradient force. Trapping was observed over the entire range of particle size from 10 μm to ~25 nm in water. Use of the new trap extends the size range of macroscopic particles accessible to optical trapping and manipulation well into the Rayleigh size regime. Application of this trapping principle to atom trapping is considered.
Citations
More filters
TL;DR: This research presents the next generation of single-beam optical traps, which promise to take optical tweezers out of the laboratory and into the mainstream of manufacturing and diagnostics and even become consumer products.
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.
4,647 citations
Book•
01 Jan 2006TL;DR: In this paper, the authors proposed a method for propagating and focusing of optical fields in a nano-optics environment using near-field optical probes and probe-sample distance control.
Abstract: 1. Introduction 2. Theoretical foundations 3. Propagation and focusing of optical fields 4. Spatial resolution and position accuracy 5. Nanoscale optical microscopy 6. Near-field optical probes 7. Probe-sample distance control 8. Light emission and optical interaction in nanoscale environments 9. Quantum emitters 10. Dipole emission near planar interfaces 11. Photonic crystals and resonators 12. Surface plasmons 13. Forces in confined fields 14. Fluctuation-induced phenomena 15. Theoretical methods in nano-optics Appendices Index.
3,772 citations
TL;DR: DsDNA molecules in aqueous buffer undergo a highly cooperative transition into a stable form with 5.8 angstroms rise per base pair, that is, 70% longer than B-form dsDNA, which may play a significant role in the energetics of DNA recombination.
Abstract: Single molecules of double-stranded DNA (dsDNA) were stretched with force-measuring laser tweezers. Under a longitudinal stress of approximately 65 piconewtons (pN), dsDNA molecules in aqueous buffer undergo a highly cooperative transition into a stable form with 5.8 angstroms rise per base pair, that is, 70% longer than B form dsDNA. When the stress was relaxed below 65 pN, the molecules rapidly and reversibly contracted to their normal contour lengths. This transition was affected by changes in the ionic strength of the medium and the water activity or by cross-linking of the two strands of dsDNA. Individual molecules of single-stranded DNA were also stretched giving a persistence length of 7.5 angstroms and a stretch modulus of 800 pN. The overstretched form may play a significant role in the energetics of DNA recombination.
2,659 citations
TL;DR: These techniques are described and illustrated with examples highlighting current capabilities and limitations of single-molecule force spectroscopy.
Abstract: Single-molecule force spectroscopy has emerged as a powerful tool to investigate the forces and motions associated with biological molecules and enzymatic activity. The most common force spectroscopy techniques are optical tweezers, magnetic tweezers and atomic force microscopy. Here we describe these techniques and illustrate them with examples highlighting current capabilities and limitations.
2,155 citations
TL;DR: Trapping and manipulation of single live motile bacteria and Escherichia coli bacteria were demonstrated in a high-resolution microscope at powers of a few milliwatts.
Abstract: Optical trapping and manipulation of viruses and bacteria by laser radiation pressure were demonstrated with single-beam gradient traps. Individual tobacco mosaic viruses and dense oriented arrays of viruses were trapped in aqueous solution with no apparent damage using approximately 120 milliwatts of argon laser power. Trapping and manipulation of single live motile bacteria and Escherichia coli bacteria were also demonstrated in a high-resolution microscope at powers of a few milliwatts.
2,107 citations
References
More filters
TL;DR: In this paper, it is hypothesized that similar acceleration and trapping are possible with atoms and molecules using laser light tuned to specific optical transitions, and the implications for isotope separation and other applications of physical interest are discussed.
Abstract: Micron-sized particles have been accelerated and trapped in stable optical potential wells using only the force of radiation pressure from a continuous laser. It is hypothesized that similar accelerations and trapping are possible with atoms and molecules using laser light tuned to specific optical transitions. The implications for isotope separation and other applications of physical interest are discussed.
4,516 citations
TL;DR: In this article, a single vertically directed focused TEM00-mode cw laser beam of ∼250 mW is sufficient to support stably a ∼20μ glass sphere.
Abstract: The stable levitation of small transparent glass spheres by the forces of radiation pressure has been demonstrated experimentally in air and vacuum down to pressures ∼1 Torr. A single vertically directed focused TEM00‐mode cw laser beam of ∼250 mW is sufficient to support stably a ∼20‐μ glass sphere. The restoring forces acting on a particle trapped in an optical potential well were probed optically by a second laser beam. At low pressures, effects arising from residual radiometric forces were seen. Possible applications are mentioned.
780 citations
624 citations
TL;DR: Use of lasers has revolutionized the study and applications of radiation pressure, and it is now possible to optically accelerate, slow, stably trap, and manipulate micrometer-sized dielectric particles and atoms.
Abstract: Use of lasers has revolutionized the study and applications of radiation pressure. Light forces have been achieved which strongly affect the dynamics of individual small particles. It is now possible to optically accelerate, slow, stably trap, and manipulate micrometer-sized dielectric particles and atoms. This leads to a diversity of new scientific and practical applications in fields where small particles play a role, such as light scattering, cloud physics, aerosol science, atomic physics, quantum optics, and high-resolution spectroscopy.
559 citations
TL;DR: In this paper, a method of stably trapping, cooling, and manipulating atoms on a continuous-wave basis using resonance radiation pressure forces is proposed using highly focused laser beams and atomic beam injection should give a very deep trap for confining single atoms or gases at temperatures
Abstract: A method of stably trapping, cooling, and manipulating atoms on a continuous-wave basis is proposed using resonance radiation pressure forces. Use of highly focused laser beams and atomic beam injection should give a very deep trap for confining single atoms or gases at temperatures \ensuremath{\sim} ${10}^{\ensuremath{-}6}$ \ifmmode^\circ\else\textdegree\fi{}K. An analysis of the saturation properties of radiation pressure forces is given.
515 citations