摘要:
To make high quality long-range periodic nanostructures in a transparent or semi-transparent substrate, the transparent or semi-transparent substrate is scanned with a linearly polarized laser beam generated by a femtosecond laser and exceeding a predetermined energy/pulse threshold along a scanning path. Sub-diffraction limit structures are formed as periodic planes of modified material in the transparent or semi-transparent substrate extending along the scanning path. The modified material can then be chemically etched to form cavities.
摘要:
To make high quality long-range periodic nanostructures in a transparent or semi-transparent substrate, the transparent or semi-transparent substrate is scanned with a linearly polarized laser beam generated by a femtosecond laser and exceeding a predetermined energy/pulse threshold along a scanning path. Sub-diffraction limit structures are formed as periodic planes of modified material in the transparent or semi-transparent substrate extending along the scanning path. The modified material can then be chemically etched to form cavities.
摘要:
A sub-micron structure is fabricated in a transparent dielectric material by focusing femtosecond laser pulses into the dielectric to create a highly tapered modified zone with modified etch properties. The dielectric material is then selectively etched into the modified zone from the direction of the narrow end of the tapered zone so that as the selective etching proceeds longitudinally into the modified zone, the progressively increasing width of the modified zone compensates for lateral etching occurring closer to the narrow end so as to produce steep-walled holes. The unetched portion of the modified zone produced by translating the laser beam close to and parallel to the bottom surface of the dielectric can serve as an optical waveguide to collect light from or deliver light to the etched channel which can contain various biological, optical, or chemical materials for sensing applications.
摘要:
A method of manipulating a microscopic quantity of material is disclosed wherein an optical fiber probe having a sharp tip with a hole fabricated therein is used to extract the material. The hole is sufficiently small that upon immersion of the sharp tip in the material a virtual seal forms to inhibit penetration of the material into the hole. A laser pulse is sent down the fiber probe to disrupt the seal and promote entry of the material into the hole. The probe can also be used in a reverse manner to deliver trapped material from the hole into a targeted region. The bole also permits an annular light intensity distribution at and near the exit of the probe tip which can be used to optically trap particles.
摘要:
In order to make alignable optical waveguides, an alignment structure is formed on at least one opposable end of the waveguides by selective chemical etching of different portions of the waveguides. The waveguides can then be brought into alignment with the alignment structure. Preferably, a pair of complementary alignment structures are formed on opposed ends of adjoining waveguides.