338 research outputs found

    SYSTEM FOR SEQUENTIALLY PROVIDING ABERATION CORRECTED ELECTROMAGNETIC RADATION TO A SPOT ON A SAMPLE AT MULTIPLE ANGLES OF INCIDENCE

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    A system for sequentially providing electromagnetic radia tion to a spot on a sample at different angles of incidence, and after reflection therefrom into a detector. The system includes a plurality of spherical mirrors, and a refractive element for correcting aberration

    Single molecule experiments in biophysics: exploring the thermal behavior of nonequilibrium small systems

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    Biomolecules carry out very specialized tasks inside the cell where energies involved are few tens of k_BT, small enough for thermal fluctuations to be relevant in many biomolecular processes. In this paper I discuss a few concepts and present some experimental results that show how the study of fluctuation theorems applied to biomolecules contributes to our understanding of the nonequilibrium thermal behavior of small systems.Comment: Proceedings of the 22nd Statphys Conference 2004 (Bangalore,India). Invited contributio

    TERAHERTZ-INFRARED ELLIPSOMETER SYSTEM, AND METHOD OF USE

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    The present invention relates to ellipsometer and polarimeter systems, and more particularly is an ellipsometer or polarimeter or the like system which operates in a frequency range between 300 GHz or lower and extending to higher than at least 1 Tera-hertz (THz), and preferably through the Infra-red (IR) range up Sh and his th. 100 THz, including: a Source Such as a backward wave oscillator, a Smith-Purcell cell; a free electron laser, or an FTIR source and a solid state device; and a detector Such as a Golay cell; abolometer or a solid state detector: and preferably including a polarization state generator comprising: an odd bounce image rotating system and a polarizer, or two polarizers; and optionally including least one compensator and/or modulator, in addition to an analyzer

    A charged particle in a magnetic field - Jarzynski Equality

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    We describe some solvable models which illustrate the Jarzynski theorem and related fluctuation theorems. We consider a charged particle in the presence of magnetic field in a two dimensional harmonic well. In the first case the centre of the harmonic potential is translated with a uniform velocity, while in the other case the particle is subjected to an ac force. We show that Jarzynski identity complements Bohr-van Leeuwen theorem on the absence of diamagnetism in equilibrium classical system.Comment: 5 pages, minor corrections made and journal reference adde

    Inferring DNA sequences from mechanical unzipping data: the large-bandwidth case

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    The complementary strands of DNA molecules can be separated when stretched apart by a force; the unzipping signal is correlated to the base content of the sequence but is affected by thermal and instrumental noise. We consider here the ideal case where opening events are known to a very good time resolution (very large bandwidth), and study how the sequence can be reconstructed from the unzipping data. Our approach relies on the use of statistical Bayesian inference and of Viterbi decoding algorithm. Performances are studied numerically on Monte Carlo generated data, and analytically. We show how multiple unzippings of the same molecule may be exploited to improve the quality of the prediction, and calculate analytically the number of required unzippings as a function of the bandwidth, the sequence content, the elasticity parameters of the unzipped strands

    Spectroscopic Ellipsometer and Polarimeter Systems

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    A spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, there being apertures before the stage for supporting a material system, and thereafter, the system being present in an environmental control chamber

    USE OF ELLIPSOMETRY AND SURFACE PLASMON RESONANCE IN MONITORING THIN FILM DEPOSITION OR REMOVAL FROM A SUBSTRATE SURFACE

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    Improved methodology for monitoring deposition or removal of material to or from a process and/or Wittness substrate Which demonstrates a negative e1 at some Wave length. The method involves detection of changes in P-polarized electromagnetism ellipsometric DELTA at SPR Resonance Angle-of-lncidence (A01) to monitor deposition of and/or removal of minute amounts of materials onto, or from, said process and/or Witness substrate. The methodology can optionally monitor ellipsometric PS1, and involves simultaneously or sequentially applying non-P-polarized electromagnetism at the same angle of incidence, or electromagnetic radiation of any polarization at a different angle-of-incidence and Wavelength to the process or Witt ness substrate and application of conventional ellipsometric analysis

    Spectroscopic Ellipsometer and Polarimeter Systems

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    A spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, there being apertures before the stage for supporting a material system, and thereafter, the system being present in an environmental control chamber

    SPECTROSCOPICELLIPSOMETER AND POLARMETER SYSTEMIS

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    A rotating compensator spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for Supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, the system being functionally present in an environmental control chamber and therefore suitable for application in wide spectral range, (for example, 130-1700 nm). Preferred compensator design involves a Substantially achromatic multiple element compensator systems wherein multiple total internal reflections enter retardance into an entered beam of electromagnetic radiation, and the elements thereof are oriented to minimize changes in the net retardance vs. the input beam angle resulting from changes in the position and/ or rotation of the system of elements

    Spectroscopic Ellipsometer and Polarimeter Systems

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    A spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, there being apertures before the stage for supporting a material system, and thereafter, the system being present in an environmental control chamber
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