Abstract: Methods and systems are disclosed that dynamically shift the wavelength of an electromagnetic (EM) beam by interacting the beam with a polariton wave having a selected polariton wave frequency.

Abstract: A spectroscopic method for characterizing a sample including: positioning the sample adjacent to a non-centrosymmetric material; directing at least one temporal pulse of coherent EM radiation into the non-centrosymmetric material to generate a polariton therein and cause EM radiation from the polariton to propagate into the sample, wherein the polariton has a frequency less than or equal to the bandwidth of the pulse; and measuring a response of the sample to the EM radiation from the polariton.

Abstract: A method for characterizing a polariton wave within a material includes: generating the polariton wave; and imaging the polariton wave with optical radiation to produce a spatially-resolved image of portions of the optical radiation affected by the polariton wave. The method can be used to identify inhomogeneities in the material, detect electrical signals within the material, or characterize a polariton wave propagating within a waveguide, e.g., a waveguide formed within a photonic crystal. The optical imaging can be based on diffraction, polarization rotation, or spectral filtering of optical probe radiation transmitted through, or reflected by, the material.

Abstract: A method for determining the thickness of a thin sample is described. The method includes the step of exciting time-dependent acoustic waveguide modes in the sample with an excitation radiation field. The acoustic waveguide modes are detected by diffracting probe radiation off a ripple morphology induced on the sample's surface by the acoustic waveguide modes. The diffracted probe radiation is then analyzed to measure phase velocities or frequencies of the acoustic waveguide modes. A thickness of the thin sample is determined by comparing the measured phase velocities or frequencies to the phase velocities or frequencies calculated from a mathematical model.

Abstract: A method and apparatus for measuring a property (e.g., thickness or composition) of at least one film in a sample (e.g., a multilayer film stack contained in a microelectronic device) is disclosed. The method features the steps of generating a coherent x-ray pulse, delivering the coherent x-ray pulse to a region on the sample to generate a signal beam, detecting the signal beam to generate an electrical signal, and analyzing the electrical signal to determine the property (e.g., thickness) of the film.

Abstract: An adhesive blend is described that can include a semi-crystalline copolymer of propylene and at least one comonomer selected from the group consisting of ethylene and at least one C4 to C20 &agr;-olefin, the copolymer having a weight average molecular weight (Mw) from about 15,000 to about 200,000; an melt index (MI) from about 7 dg/min to about 3000 dg/min as measured by ASTM D 1238(B), and a (Mw/Mn) of approximately 2. Various production processes are also described. Also described are adhesive compositions and methods for making adhesive compositions having polymers or polymer blends with melt flow rates (MFRs) equal to and above 250 dg/min. at 230 NC. Certain specific embodiments of the invention involve the use of a free radical initiator, e.g., a peroxide.

Abstract: The invention relates to novel adhesive alpha-olefin inter-polymers which are largely amorphous and have a Theological behavior that makes them suitable for adhesive use, both without and with minimzed amounts of tackifying resins. Specifically, the invention poly-alpha olefin inter-polymer may be composed of A) from 60 to 94 % of units derived from one alpha mono-olefin having from 3 to 6 carbon atoms and B) from 6 to 40 mol % of units derived from one or more other mono-olefins having from 4 to 10 carbon atoms and at least one carbon atom more than A); and C) optionally from 0 to 10 mol % of units derived from another copolymerizable unsaturated hydrocarbon, different from A) and B); the diad distribution of component A in the polymer as determined by 13C NMR as described herein showing a ratio of experimentally determined diad distribution over the calculated Bernoullian diad distribution of less than 1.

Abstract: The invention features methods and systems for optical correlation of ultrashort optical waveforms, e.g., pulses. The optical waveform passes through a diffractive optic, e.g., a mask or grating, to generate multiple sub-beams corresponding to different diffractive orders. At least two of the sub-beams are then imaged onto the sample to produce a desired crossing pattern. To perform the correlation, the diffracted sub-beams are variably delayed relative to one another prior to overlapping on the sample. The sample generates a signal beam in response to the overlapping sub-beams, the signal beam providing a correlation between the sub-beams for each of the variable delays.

Abstract: A method for determining the thickness of a thin sample is described. The method includes the step of exciting time-dependent acoustic waveguide modes in the sample with an excitation radiation field. The acoustic waveguide modes are detected by diffracting probe radiation off a ripple morphology induced on the sample's surface by the acoustic waveguide modes. The diffracted probe radiation is then analyzed to measure phase velocities or frequencies of the acoustic waveguide modes. A thickness of the thin sample is determined by comparing the measured phase velocities or frequencies to the phase velocities or frequencies calculated from a mathematical model.

Abstract: The invention features methods and systems for processing signals by optically manipulating polaritons. In one embodiment, the signal processing method includes: converting a plurality of spatially separated input signals into polaritons that propagate in a signal processing material; optically manipulating the polaritons at a plurality of spatially separated locations in the signal processing material; and converting the manipulated polaritons into at least one output signal. In another embodiment, the signal processing method includes: converting an input signals into a polariton that propagates in a non-conductive signal processing material; optically manipulating the polariton as it propagates in the signal processing material; and converting the manipulated polaritons into an electrical output signal at an interface between the signal processing material and a conductive path in another material.

Abstract: An apparatus for measuring a property of a structure comprising at least one layer, the appratus including a light source that produces an optical pulse having a duration of less than 10 ps; a diffractive element that receives the optical pulse and diffracts it to generate at least two excitation pulses; an optical system that spatially and temporally overlaps at least two excitation pulses on or in the structure to form an excitation pattern, containing at least two light regions, that launches an acoustic wave having an out-of-plane component that propagates through the layer, reflects off a lower boundary of the layer, and returns to a surface of the structure to modulate a property of the structure; a light source that produces a probe pulse that diffracts off the modulated property to generate at least one signal pulse; a detector that receives at least one signal pulse and in response generates a light-induced electrical signal; and an analyzer that analyzes the light-induced electrical signal to measur

Abstract: A method for introducing desired electromagnetic radiation into a photonic crystal having a photonic bandgap and at least one defect, wherein the desired electromagnetic radiation has a frequency within the photonic bandgap. The method includes the steps of: delivering source electromagnetic radiation having an electromagnetic frequency outside the photonic bandgap to the defect; and generating the desired electromagnetic radiation at the defect in response to the source electromagnetic radiation.

Abstract: The invention features a method for detecting a subsurface defect in a thin film structure. The method includes: optically generating an acoustic wave in a first spatial region of the film; optically measuring a time-dependent reflection of the acoustic wave from subsurface features in the film to produce a time-dependent signal; and analyzing the signal to detect an existence of the defect. The optically measuring step can include measuring the diffraction of a probe beam from the reflected acoustic wave. The analyzing step can include comparing the measured signal to a reference signal for defect-free structure.

Abstract: A method for determining the thickness of a thin sample is described. The method includes the step of exciting time-dependent acoustic waveguide modes in the sample with an excitation radiation field. The acoustic waveguide modes are detected by diffracting probe radiation off a ripple morphology induced on the sample's surface by the acoustic waveguide modes. The diffracted probe radiation is then analyzed to measure phase velocities or frequencies of the acoustic waveguide modes. A thickness of the thin sample is determined by comparing the measured phase velocities or frequencies to the phase velocities or frequencies calculated from a mathematical model.

Abstract: An optical modulating system which allows modulation of a single light beam with a spatially filtering mask to form a spatially periodic, time-dependent excitation field. Once generated, the field can be used to induce a transient grating in a sample. The optical modulating system is additionally configured to automatically orient a probe beam at the Bragg angle, thereby allowing the intensity of the probe beam diffracted off the induced grating to be maximized. Measurement of the diffracted probe beam allows, for example, determination of mechanical, thermal, electrical, and optical properties of the sample.

Abstract: A light modulator is described which generates an output optical field from an input optical field. The light modulator features first and second polarization-rotating elements which are directly attached to one another. Each element contains an array of pixels including liquid crystals aligned along a specific axis. During operation, the pixels are biased to rotate the liquid crystals. For a particular polarization, the phase and amplitude profiles of the input optical field passing through the pixel array can be arbitrarily and independently controlled across an aperture of the light modulator.

Abstract: A method and device for shaping both the temporal and spatial profiles of an input optical pulse to generate an output optical waveform are described. The method includes the step of dispersing the spectral frequencies of the input pulse. These frequencies are then focused with a cylindrical lens to form a two-dimensional optical field. The field is imaged on a mask featuring a two-dimensional array of pixels. The amplitudes, phases, or phases and amplitudes of the two-dimensional optical field are then filtered with the mask. The filtered spectral frequencies are then recombined to form the collective temporal profile of the output waveform. The two-dimensional optical field is then imaged in a sample plane to form the spatially coherent regions.

Abstract: Anisotropic mechanical properties of thin films are measured by exciting time-dependent waveguide acoustic modes in the thin film sample with a pair of excitation pulses from an excitation laser. The waveguide acoustic modes are then optically detected by diffracting a probe laser beam off the excited modes. The probe beam is detected to generate an electronic signal. The anisotropic moduli and related properties in the film are determined by analyzing the electronic signal using a mathematical inversion procedure.

Abstract: An exercise device includes a base having a support column vertically extending therefrom. A handle assembly is rotatably mounted to one side of the column about a horizontal axis passing through the column. The handle assembly is linked to a first swingable housing on the opposed side of the column with rotation of the handle assembly causing a swingable movement of the first housing. An elastic band extends from the first housing and is wound about guide pins in a second housing fixed to the column so that movement of the first housing is resisted by the elastic band. The tension of the band is regulated by first and second band take up reels in the first housing, the reels being rotatable by a dial extending from the first housing. Rotation of the reels winds or unwinds the band ends therefrom so as to increase or decrease the tension in the elastic.

Abstract: Samples such as thin polymeric films are analyzed using optically induced phonons by excitation of the sample using radiation preferably absorbed by the sample and probe radiation, preferably not absorbed by the sample, that is diffracted from the surface of the sample. The pulse width of the probe is preferably on the order of the detectable diffraction signal so that the phonon decay from each excitation pulse can be detected and analyzed. The technique is applicable to various samples by inducing a ripple morphology on the sample surface and detection of light diffracted substantially from surface ripple.