James J. Butler

Diffraction properties of highly birefringent liquid-crystal composite gratings

We have fabricated electrically switchable holographic gratings, using Polaroid Corporations DMP-128 photopolymer filled with the nematic liquid crystal E7. It is shown that a coupled-wave theory that includes the effects of the birefringence of the liquid crystal must be used to explain the diffraction properties of these anisotropic volume gratings. Furthermore, a detailed comparison of theory and experiment provides information about the alignment of the liquid crystal within the polymer host.

Transmission properties of refractive index-shifted Bragg gratings

Abstract We present an analysis of the transmission properties of index-shifted Bragg gratings. Theoretical predictions of the transmission properties of these gratings are obtained using a generalized transfer matrix method. Our theoretical predictions show that a precise modification of the average refractive index of Bragg gratings can lead to the generation of narrowband transmission windows within a broad low transmission band. The theoretical predictions are compared to experimental results obtained with fiber Bragg gratings.

Optical limiting properties of nonlinear multimode waveguides

An experimental investigation of the transmission of multimode capillary waveguides with a nonlinear absorber in the core shows an enhanced nonlinear absorption relative to the same length of bulk material. The results are consistent with partial mode filling within the cores of the waveguides. This study confirms the promising optical limiting capabilities of multimode nonlinear waveguides and implies that the mode structure should be considered in the design and evaluation of capillary array optical limiters.

Optical limiting properties of nonlinear multimode waveguide arrays

An experimental investigation of the transmission of multimode capillary waveguide arrays containing a liquid nonlinear absorber shows an enhanced nonlinear response relative to that found in a single waveguide and to the same length of bulk material. Comparison of the nonlinear response of arrays with different pitch to diameter (d/Lambda) ratios confirm that both the intensity distribution within an individual waveguide and coupling between the elements of the array influence the overall nonlinear response.

Near IR nonlinear absorption of an organic supermolecule [Invited]

The photophysics of bis(terpyridyl)osmium-(porphinato)zinc-bis(terpyridyl)osmium (OsPZnOs), a D-π-A-π-D symmetric supermolecule, were investigated in the femtosecond and nanosecond regimes. The supermolecule exhibits a two-photon absorption (δpeak ~900 GM) in the near IR (900-1300 nm) and optical pumping by two-photon absorption leads to a broad excited state absorption (σpeak ~1.1 × 10−16 cm2) in the same near IR region. Since the excited state has a long lifetime, OsPZnOs exhibits a strong nanosecond nonlinear absorption in this region. That nonlinear absorption is substantially enhanced when OsPZnOs is incorporated into a multimode waveguide. When two-photon pumping is the dominant mechanism, an additional enhancement of up to ~100 × in the nonlinear absorption is observed in a microchannel waveguide. OsPZnOs is a promising material for photonic applications such as optical noise suppression and optical limiting in the near IR.

Optical properties of solid-core photonic crystal fibers filled with nonlinear absorbers

A theoretical and experimental investigation of the transmission of solid-core photonic crystal fibers (PCFs) filled with nonlinear absorbers shows a sharp change in the threshold for optical limiting and in leakage loss as the refractive index of the material in the holes approaches that of the glass matrix. Theoretical calculations of the mode profiles and leakage loss of the PCF are in agreement with experimental results and indicate that the change in limiting response is due to the interaction of the evanescent field of the guided mode with the nonlinear absorbers in the holes.

Optical limiting in solid-core photonic crystal fibers

Optical limiting in solid-core photonic crystal fibers filled with reverse-saturable absorbers has been observed. A sharp change in limiting threshold was found for materials in the fiber holes with refractive indices near n = 1.44.

Index-shifted Bragg gratings

We present an analysis of the transmission properties of index-shifted Bragg gratings. Theoretical predictions of the transmission properties of these gratings are obtained using a generalized transfer matrix method. The predictions show that a precise modification of the refractive index profile of Bragg gratings can lead to the generation of narrowband transmission windows within a low transmission band.

Front Matter: Volume 10402

ix Conference Committee PLENARY SESSION 7081 02 Measurement science for climate remote sensing [7081-53] G. T. Fraser, S. W. Brown, R. U. Datla, B. C. Johnson, K. R. Lykke, J. P. Rice, National Institute of Standards and Technology (United States) PRELAUNCH CALIBRATION 7081 03 Vacuum compatible large uniform-radiance source for ground calibration of satellite cameras inside a thermal vacuum environment [7081-01] A. V. Arecchi, SphereOptics LLC (United States); S. Pal, Indian Space Research Organization (India); J. W. Jablonski, M. Gervais, M. Gugliotta, SphereOptics LLC (United States); H. Seth, A. Bhardwaj, H. S. Sahoo, Indian Space Research Organization (India) 7081 04 Design and validation of a transfer radiometer [7081-02] N. Anderson, K. Thome, S. Biggar, J. S. Czapla-Myers, College of Optical Sciences, Univ. of Arizona (United States) 7081 06 Pre-launch performance characterization of EOS-C camera [7081-04] Y.-W. Choi, S. Kang, J. Yun, J. Kim, M. Kang, S. Jeong, H. Kim, J. Song, E.-E. Kim, Satrec Initiative (South Korea) 7081 07 BRDF study of gray-scale Spectralon [7081-05] G. T. Georgiev, Science Systems and Applications, Inc. (United States); J. J. Butler, NASA Goddard Space Flight Ctr. (United States) 7081 08 Pre-launch optical tests of MODIS and MISR [7081-06] E. Waluschka, NASA Goddard Space Flight Ctr. (United States); C. J. Bruegge, Jet Propulsion Lab. (United States); X. Xiong, NA SA Goddard Space Flight Ctr. (United States) MODIS I 7081 09 MODIS along-scan direction Line Spread Function (LSF) modeling and verification using the Integration and Alignment Collimator (IAC) [7081-07] N. Che, T. Choi, Science Systems and Applications, Inc. (United States); X. Xiong, NASA Goddard Space Flight Ctr. (United States); D. Moyer, Aerospace Corp. (United States) 7081 0A On-orbit aqua MODIS modulation transfer function trending in along-scan from the Spectro-Radiometric Calibration Assembly [7081-08] T. Choi, N. Che, Science Systems and Applications, Inc. (United States); X. Xiong, NASA Goddard Space Flight Ctr. (United States)

Single crystal diamond boron 'delta doped' nanometric layers for 2D electronic devices(Conference Presentation)

Use of diamond as a semiconductor material suffers from the high activation energy of all known impurity dopants (0.37 eV for Boron, 0.6 eV for Phosphorous). To achieve the simultaneous carrier concentration and mobility desired for devices operating at room temperature, growth of a nanometric thick ‘delta’ layer doped to above the metal insulator transition adjacent to high mobility intrinsic material can provide a 2D high mobility conduction layer. Critical to obtaining the enhanced mobility of the carriers in the layer next to the ‘delta’ doped layer is the abruptness of the doping interface. Single and multiple nanometer thick epitaxial layers of heavily boron ‘delta’ doped diamond have been grown on high quality, intrinsic lab grown diamond single crystals. These layers were grown in a custom microwave plasma activated chemical vapor deposition reactor based on a rapid reactant switching technique. Characterization of the ‘delta’ layers by various analytical techniques will be presented. Electrical measurements demonstrating enhanced hole mobility (100 to 800 cm2/V sec) as well as other electrical characterizations will be presented.