Abstract:
A technique to guide a micro- or nano-scale particle uses the wavelengths of light beams to control the direction of motion of the particle. In this technique, an optical asymmetry is introduced into the particle to form a composite particle. The composite particle includes two faces that preferentially absorb light of different wavelengths, independent of the particle orientation. The difference in absorption spectra of the two faces creates a bidirectional and local thermal gradient that is externally switchable by changing the wavelength of the incident light beams. This thermal gradient induces a thermophoretic drift that moves the composite particle. A two-faced nanoparticle can be guided using the optically induced thermophoretic drift as the propulsion mechanism.
Abstract:
An electromagnetic device for accelerating electrically neutral molecules of a substance is characterized by the fact of comprising: a Treating Tube (14) in non-conducting material, into which the substance to treat is introduced; static electromagnetic circuits that surround the above Treating Tube exerting on the substance to treat electromagnetic actions which push it axially, with utilization of the dipolar electric moment of the molecules. The treating method of the molecules accelerates these molecules utilizing their weak dipolar electric moment, subjecting them to a combination of a magnetic field and an electric one or, in alternative, of a magnetic field and one at Hertz waves, alternating and isofrequential, utilizing the Lorentz force of electrology.
Abstract:
A static electromagnetic device for accelerating electrically neutral molecules utilizing their dipolar electric moment is characterized by the fact of comprising comprise: a treating tube in non-conducting material, internally empty or filled with inert material, into which a (fluid or solid) substance to treat is introduced; static electromagnetic circuits that surround the above treating tube exerting on the substance to treat electromagnetic actions that push it axially.
Abstract:
A new optical tweezer technology, based on optical antennas. Optical antennas are metallic nanostructures that, when illuminated at their resonant wavelength, generate enhanced optical fields with subwavelength spatial extent. The trapping of single virus particles using optical antennas with milliwatt laser powers, in volumes with dimensions of tens of nanometers. This represents a reduction in the necessary laser power by -2-3 orders of magnitude. The spatial resolution provided by the antennas will enable nanostructures to be manipulated in a highly precise manner. Optical antennas remove the need for costly objective lenses used in conventional tweezers to provide the gradient forces necessary for stable trapping. Traps can be produced on a chip by high-resolution lithography, enabling microsystems with thousands of traps.
Abstract:
The present invention employs a beam steering apparatus to isolate valuable cells from others cells, tissues, and contaminants. In one embodiment, the system balances optical trapping agains flow to parallelize cell sorting under the flexible control of computer program-directed traps which differentially manipulate cells based on their composition or labels to direct separation.
Abstract:
Small particles 1, for example 5 mu m diameter microspheres or cells, within, and moving with, a fluid 2, normally water, that is flowing within microfluidic channels 3 within a radiation-transparent substrate 4, typically molded PDMS clear plastic, are selectively manipulated, normally by being pushed with optical pressures forces, with a laser light switching beam 5, preferably as arises from VCSELs operating in Laguerre-Gaussian mode, at branching junctions, such as an "X", in the microfluidic channels 3 so as to enter into selected downstream branches OUTPUT 1, OUPUT 2, thereby realizing switching and sorting of particles 1, including in parallel. Transport of the small particles 1 thus transpires by microfluidics while manipulation in the manner of optical tweezers arises either from pushing due to optical scattering force, or from pulling due to an attractive optical gradient force. Whether pushed or pulled, the particles within the flowing fluid may be optically sensed, and highly-parallel. Low-cost, cell- and particle-analysis devices efficiently realized, including as integrated on bio-chips.
Abstract:
An apparatus and method for manipulating small dielectric particles. The apparatus and method involves use of a diffractive optical element (40) which receives a laser beam and forms a plurality of light beams. These light beams are operated on by a telescope lens system (34) and then an objective lens element (20) to create an array of optical traps (50) for manipulating small dielectric particles.
Abstract:
A method of controlling the amplitude-phase characteristics of an atomic wave involves allowing a beam of atoms to pass through a region of spatially non-homogeneous electromagnetic radiation produced by the superposition of an electromagnetic wave from any object and a planar reference electromagnetic wave. The atom beam is directed along or against the reference electromagnetic wave and, once an atomic wave has been obtained which imitates the electromagnetic wave from the object, an image of the object is recreated in the atom beams, compensation for the gravity acting on the atoms being applied in the region of distribution of the atoms.
Abstract:
Tightly focused beams of laser light are used as "optical tweezers" to trap and manipulate polarizable objects such as microspheres of glass or latex with diameters on the order of 4.5 mu m. When analytes are allowed to adhere to the microspheres, small quantities of these analytes can be manipulated, thus allowing their detection and quantitation even when amounts and concentrations of the analytes are extremely small. Illustrative examples include measuring the strength needed to break antibody-antigen bonds and the detection of DNA sequences.
Abstract:
The invention pertains to a device for the three dimensional cooling of an atom vapour, characterised in that it comprises a cell (2) for containing the atom vapour to be cooled and means (12) for transmitting isotropic laser radiation at least to a portion of the cell. The invention is particularly useful for atomic clocks.