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Poly(3-Hexylthiophene) Crystalline Nanoribbon Network For Organic Field Effect Transistors, M. Arif, Jianhua Liu, Lei Zhai, Saiful I. Khondaker
Poly(3-Hexylthiophene) Crystalline Nanoribbon Network For Organic Field Effect Transistors, M. Arif, Jianhua Liu, Lei Zhai, Saiful I. Khondaker
Faculty Bibliography 2010s
We report on the fabrication of crystalline nanoribbon network field effect transistors (FETs) using low molecular weight (M(W)) poly(3-hexylthiophene) (P3HT) with different surface treatments and compare with thin film FETs cast from the same M(W) regioregular P3HT. Nanoribbon FET shows improved performance with a maximum mobility of 0.012 cm(2)/V s and current on/off ratios of 6.5x10(4) due to unique crystalline structure and morphology. With various surface treatments, the nanoribbon FETs show less variation in device mobilities, while thin film FETs show more than ten times variation in device mobilities and up to 100 times change in current on/off ratios.
Graphene-Like Silicon Nanoribbons On Ag(110): A Possible Formation Of Silicene, Bernard Aufray, Abdelkader Kara, Sébastien Vizzini, Hamid Oughaddou, Christel Léandri, Benedicte Ealet, Guy Le Lay
Graphene-Like Silicon Nanoribbons On Ag(110): A Possible Formation Of Silicene, Bernard Aufray, Abdelkader Kara, Sébastien Vizzini, Hamid Oughaddou, Christel Léandri, Benedicte Ealet, Guy Le Lay
Faculty Bibliography 2010s
Scanning tunneling microscopy (STM) and ab initio calculations based on density functional theory (DFT) were used to study the self-aligned silicon nanoribbons on Ag(110) with honeycomb, graphene-like structure. The silicon honeycombs structure on top of the silver substrate is clearly observed by STM, while the DFT calculations confirm that the Si atoms adopt spontaneously this new silicon structure.
Dispersion Measurements Of A 1.3 Mu M Quantum Dot Semiconductor Optical Amplifier Over 120 Nm Of Spectral Bandwidth, M. Bagnell, J. Davilla-Rodriguez, A. Ardey, P. J. Delfyett
Dispersion Measurements Of A 1.3 Mu M Quantum Dot Semiconductor Optical Amplifier Over 120 Nm Of Spectral Bandwidth, M. Bagnell, J. Davilla-Rodriguez, A. Ardey, P. J. Delfyett
Faculty Bibliography 2010s
Group delay and higher order dispersion measurements are conducted on a 1.3 mu m quantum dot semiconductor optical amplifier at various injection currents. White-light spectral interferometry is performed, along with a wavelet transform to recover the group delay. The group delay, group velocity dispersion, and higher order dispersion terms are quantified. The measurement spans both ground state and first excited state transitions, ranging from 1200 to 1320 nm. The group velocity dispersion, beta(2), is found to be -6.3x10(3) fs(2) (7.6 fs/nm) at an injection current of 500 mA.
B Diffusion In Implanted Ni2si And Nisi Layers, I. Blum, A. Portavoce, L. Chow, D. Mangelinck, K. Hoummada, G. Tellouche, V. Carron
B Diffusion In Implanted Ni2si And Nisi Layers, I. Blum, A. Portavoce, L. Chow, D. Mangelinck, K. Hoummada, G. Tellouche, V. Carron
Faculty Bibliography 2010s
B diffusion in implanted Ni2Si and NiSi layers has been studied using secondary ion mass spectrometry, and compared to B redistribution profiles obtained after the reaction of a Ni layer on a B-implanted Si(001) substrate, in same annealing conditions (400-550 degrees C). B diffusion appears faster in Ni2Si than in NiSi. The B solubility limit is larger than 10(21) atom cm(-3) in Ni2Si, while it is similar to 3x10(19) atom cm(-3) in NiSi. The solubility limit found in NiSi is in agreement with the plateau observed in B profiles measured in NiSi after the reaction of Ni on B-implanted Si.
Evidence Of Graphene-Like Electronic Signature In Silicene Nanoribbons, Paola De Padova, Claudio Quaresima, Carlo Ottaviani, Polina M. Sheverdyaeva, Paolo Moras, Carlo Carbone, Dinesh Topwal, Bruno Olivieri, Abdelkader Kara, Hamid Oughaddou, Bernard Aufray, Guy Le Lay
Evidence Of Graphene-Like Electronic Signature In Silicene Nanoribbons, Paola De Padova, Claudio Quaresima, Carlo Ottaviani, Polina M. Sheverdyaeva, Paolo Moras, Carlo Carbone, Dinesh Topwal, Bruno Olivieri, Abdelkader Kara, Hamid Oughaddou, Bernard Aufray, Guy Le Lay
Faculty Bibliography 2010s
We report on the electronic properties of straight, 1.6 nm wide, silicene nanoribbons on Ag(110), arranged in a one-dimensional grating with a pitch of 2 nm, whose high-resolution scanning tunneling microscopy images reveal a honeycomb geometry. Angle-resolved photoemission shows quantum confined electronic states of one-dimensional character. The silicon band dispersion along the direction of the nanoribbons suggests a behavior analogous to the Dirac cones of graphene on different substrates.
Investigation Of The Behavior Of Serum And Plasma In A Microfluidics System, J. Caroline Henderson, Michele Yacopucci, Chang Ju Chun, Keith Lenghaus, Frank Sommerhage, James J. Hickman
Investigation Of The Behavior Of Serum And Plasma In A Microfluidics System, J. Caroline Henderson, Michele Yacopucci, Chang Ju Chun, Keith Lenghaus, Frank Sommerhage, James J. Hickman
Faculty Bibliography 2010s
There are common problems with adsorption of analytes on the surfaces of microfluidic systems with physiological samples such as blood serum, plasma, and urine. The authors' investigation involves the interaction of serum components with fused-silica surfaces under various flow regimes in microcapillaries. Their focus will include the individual components of serum as well as fresh whole serum. The authors studied the whole serum components in our microfluidic system to uncover the responses of proteins in capillary and microchannel surfaces when influenced by the highly variable serum constituents. They have observed the whole serum with a total protein assay by using …
Multiplexed Biomarker Detection Using X-Ray Fluorescence Of Composition-Encoded Nanoparticles, Mainul Hossain, Chaoming Wang, Ming Su
Multiplexed Biomarker Detection Using X-Ray Fluorescence Of Composition-Encoded Nanoparticles, Mainul Hossain, Chaoming Wang, Ming Su
Faculty Bibliography 2010s
Multiple DNA and protein biomarkers have been detected based on characteristic x-ray fluorescence of a panel of metal and alloy nanoparticles, which are modified with ligands of biomarkers to create a one-to-one correspondence and immobilized on ligand-modified substrates after forming complexes with target biomarkers in three-strand or sandwich configuration. By determining the presence and concentration of nanoparticles using x-ray fluorescence, the nature and amount of biomarkers can be detected with limits of 1 nM for DNA and 1 ng/ml for protein. By combining high penetrating ability of x-rays, this method allows quantitative imaging of multiple biomarkers.
Crystal Coherence Length Effects On The Infrared Optical Response Of Mgo Thin Films, J. F. Ihlefeld, J. C. Ginn, D. J. Shelton, V. Matias, M. A. Rodriguez, P. G. Kotula, J. F. Carroll Iii, G. D. Boreman, P. G. Clem, M. B. Sinclair
Crystal Coherence Length Effects On The Infrared Optical Response Of Mgo Thin Films, J. F. Ihlefeld, J. C. Ginn, D. J. Shelton, V. Matias, M. A. Rodriguez, P. G. Kotula, J. F. Carroll Iii, G. D. Boreman, P. G. Clem, M. B. Sinclair
Faculty Bibliography 2010s
The role of crystal coherence length on the infrared optical response of MgO thin films was investigated with regard to Reststrahlen band photon-phonon coupling. Preferentially (001)-oriented sputtered and evaporated ion-beam assisted deposited thin films were prepared on silicon and annealed to vary film microstructure. Film crystalline coherence was characterized by x-ray diffraction line broadening and transmission electron microscopy. The infrared dielectric response revealed a strong dependence of dielectric resonance magnitude on crystalline coherence. Shifts to lower transverse optical phonon frequencies were observed with increased crystalline coherence. Increased optical phonon damping is attributed to increasing granularity and intergrain misorientation.
Theoretical Calculations Of Hydrogen Adsorption By Sno2 (110) Surface: Effect Of Doping And Calcination, Talgat M. Inerbaev, Yoshiyuki Kawazoe, Sudipta Seal
Theoretical Calculations Of Hydrogen Adsorption By Sno2 (110) Surface: Effect Of Doping And Calcination, Talgat M. Inerbaev, Yoshiyuki Kawazoe, Sudipta Seal
Faculty Bibliography 2010s
A pseudopotential plane-wave based density functional theory simulations of the hydrogen adsorption on rutile SnO2 (110) surface is reported. It is found that on doping with trivalent indium, the surface becomes unstable due to the formation of bridging oxygen vacancies. At sufficiently low doping level, the surface stabilizes at an oxygen vacancy to indium ratio of 1:2. Our calculations predict that at a higher doping level of 9 at. %, this ratio becomes larger, and point out a way to synthesize p-type conducting SnO2 thin films. The binding energy of SnO2 (110) surface with adsorbed hydrogen atoms display a maximum …
Space Charge Limited Conduction With Exponential Trap Distribution In Reduced Graphene Oxide Sheets, Daeha Joung, A. Chunder, Lei Zhai, Saiful I. Khondaker
Space Charge Limited Conduction With Exponential Trap Distribution In Reduced Graphene Oxide Sheets, Daeha Joung, A. Chunder, Lei Zhai, Saiful I. Khondaker
Faculty Bibliography 2010s
We elucidate on the low mobility and charge traps of the chemically reduced graphene oxide (RGO) sheets by measuring and analyzing temperature dependent current-voltage characteristics. The RGO sheets were assembled between source and drain electrodes via dielectrophoresis. At low bias voltage the conduction is Ohmic while at high bias voltage and low temperatures the conduction becomes space charge limited with an exponential distribution of traps. We estimate an average trap density of 1.75 x 10(16) cm(-3). Quantitative information about charge traps will help develop optimization strategies of passivating defects in order to fabricate high quality solution processed graphene devices.
Low Temperature Deformation Of The R-Phase In A Nitife Shape Memory Alloy, V. B. Krishnan, S. B. Shmalo, C. R. Rathod, M. A. M. Bourke, R. Vaidyanathan
Low Temperature Deformation Of The R-Phase In A Nitife Shape Memory Alloy, V. B. Krishnan, S. B. Shmalo, C. R. Rathod, M. A. M. Bourke, R. Vaidyanathan
Faculty Bibliography 2010s
Deformation in the P3 phase (R-phase) of NiTiFe was investigated by in situ neutron diffraction during compressive loading at cryogenic temperatures. At 216 K, upon loading the R-phase detwinned and subsequently underwent a reversible stress-induced transformation to the B19' phase (martensite). At 92 K on the other hand, detwinning was suppressed and the stress-induced martensite formed did not transform back upon unloading. The experiments also directly observed a hitherto theoretically predicted B33 phase. Rietveld refinement of the neutron diffraction spectra were used to determine lattice parameters of the B33 and R-phases. Plane-specific elastic moduli were also determined for the R-phase.
Structural Morphology Of Acoustically Levitated And Heated Nanosilica Droplet, Ranganathan Kumar, Erick Tijerino, Abhishek Saha, Saptarshi Basu
Structural Morphology Of Acoustically Levitated And Heated Nanosilica Droplet, Ranganathan Kumar, Erick Tijerino, Abhishek Saha, Saptarshi Basu
Faculty Bibliography 2010s
We study the vaporization and precipitation dynamics of a nanosilica encapsulated water droplet by levitating it acoustically and heating it with a CO(2) laser. For all concentrations, we observe three phases: solvent evaporation, surface agglomeration, and precipitation leading to bowl or ring shaped structures. At higher concentrations, ring reorientation and rotation are seen consistently. The surface temperature from an infrared camera is seen to be dependent on the final geometrical shape of the droplet and its rotation induced by the acoustic field of the levitator. With nonuniform particle distribution, these structures can experience rupture which modifies the droplet rotational speed.
Epitaxial Growth Of A Silicene Sheet, Boubekeur Lalmi, Hamid Oughaddou, Hanna Enriquez, Abdelkader Kara, Sébastien Vizzini, Bénidicte Ealet, Bernard Aufray
Epitaxial Growth Of A Silicene Sheet, Boubekeur Lalmi, Hamid Oughaddou, Hanna Enriquez, Abdelkader Kara, Sébastien Vizzini, Bénidicte Ealet, Bernard Aufray
Faculty Bibliography 2010s
Using atomic resolved scanning tunneling microscopy, we present here the experimental evidence of a silicene sheet (graphenelike structure) epitaxially grown on a close-packed silver surface [Ag(111)]. This has been achieved via direct condensation of a silicon atomic flux onto the single-crystal substrate in ultrahigh vacuum conditions. A highly ordered silicon structure, arranged within a honeycomb lattice, is synthesized and present two silicon sublattices occupying positions at different heights (0.02 nm) indicating possible sp(2)-sp(3) hybridizations.
Superconducting Properties Of A Two-Dimensional Doped Semiconductor, V. M. Loktev, V. Turkowski
Superconducting Properties Of A Two-Dimensional Doped Semiconductor, V. M. Loktev, V. Turkowski
Faculty Bibliography 2010s
This is a study of the superconducting properties of a two-dimensional model with an additional (insulating) gap Delta(ins) that depends on temperature and doping. In particular, we study the doping dependence of the Berezinskii-Kosterlitz-Thouless critical temperature T(c) and the superconducting pseudogap temperature T(c)(MF) for different values of Delta(ins) by taking hydrodynamic fluctuations of the superconducting order parameter into account. We show that the gap Delta(ins) affects the values of the superconducting gap and the temperatures T(c) and T(c)(MF) within the range of carrier densities where the Delta(ins) approaches zero. In particular, the derivatives of these quantities have a jump in …
Optical Transmission Properties Of C-Shaped Subwavelength Waveguides On Silicon, O. Lopatiuk-Tirpak, J. Ma, S. Fathpour
Optical Transmission Properties Of C-Shaped Subwavelength Waveguides On Silicon, O. Lopatiuk-Tirpak, J. Ma, S. Fathpour
Faculty Bibliography 2010s
Optical properties of C-shaped subwavelength waveguides in metallic (silver) films on silicon substrates are studied in the range of 0.6-6 mu m. Power throughput and resonant wavelengths of several transmission modes are studied by varying the waveguide length (or metal thickness). Among three types of transmission modes, the fundamental order of the Fabry-Perot-type mode was shown to attain remarkably high power throughputs (as high as 12). With optimized design of the aperture, the resonant wavelength of this mode occurs in the 1-2 mu m wavelength range, suggesting that such apertures can be utilized to achieve plasmonic-enhanced silicon photonic devices at …
Synergistic Effect Of Carbon Nanofiber And Carbon Nanopaper On Shape Memory Polymer Composite, Haibao Lu, Yanju Liu, Jihua Gou, Jinsong Leng, Shanyi Du
Synergistic Effect Of Carbon Nanofiber And Carbon Nanopaper On Shape Memory Polymer Composite, Haibao Lu, Yanju Liu, Jihua Gou, Jinsong Leng, Shanyi Du
Faculty Bibliography 2010s
The present work studies the synergistic effect of carbon nanofiber (CNF) and carbon nanopaper on the shape recovery of shape memory polymer (SMP) composite. The combination of CNF and carbon nanopaper was used to improve the thermal and electrical conductivities of the SMP composite. The carbon nanopaper was coated on the surface of the SMP composite in order to achieve the actuation by electrical resistive heating. CNFs were blended with the SMP resin to improve the thermal conductivity to facilitate the heat transfer from the nanopaper to the underlying SMP composite to accelerate the electroactive responses.
Superelastic Response Of 111 And 101 Oriented Niti Micropillars, R. M. Manjeri, S. Qiu, N. Mara, A. Misra, R. Vaidyanathan
Superelastic Response Of 111 And 101 Oriented Niti Micropillars, R. M. Manjeri, S. Qiu, N. Mara, A. Misra, R. Vaidyanathan
Faculty Bibliography 2010s
A combination of microcompression experiments on single crystal micron-scaled pillars of NiTi of known orientations and in situ neutron diffraction during loading of the same NiTi but in bulk, polycrystalline form are carried out to understand the stress-induced transformation associated with superelasticity at reduced length scales. At the length scales investigated, there is evidence through this work of a fully reversible stress-induced transformation from B2 to B19' NiTi that does not involve additional dislocation activity or irrecoverable strains. The orientation dependence of the elastic deformation of the 82 phase, the onset of its transformation to the B19' phase, the gradient …
Temperature Dependence Of Plasmonic Terahertz Absorption In Grating-Gate Gallium-Nitride Transistor Structures, A. V. Muravjov, D. B. Veksler, V. V. Popov, O. V. Polischuk, N. Pala, X. Hu, R. Gaska, H. Saxena, R. E. Peale, M. S. Shur
Temperature Dependence Of Plasmonic Terahertz Absorption In Grating-Gate Gallium-Nitride Transistor Structures, A. V. Muravjov, D. B. Veksler, V. V. Popov, O. V. Polischuk, N. Pala, X. Hu, R. Gaska, H. Saxena, R. E. Peale, M. S. Shur
Faculty Bibliography 2010s
Strong plasmon resonances have been observed in the terahertz transmission spectra (1-5 THz) of large-area slit-grating-gate AlGaN/GaN-based high-electron-mobility transistor (HEMT) structures at temperatures from 10 to 170 K. The resonance frequencies correspond to the excitation of plasmons with wave vectors equal to the reciprocal lattice vectors of the metal grating, which serves both as a gate electrode for the HEMT and a coupler between plasmons and incident terahertz radiation. Wide tunability of the resonances by the applied gate voltage demonstrates potential of these devices for terahertz applications.
Reconstruction Of Planar Conductivities In Subdomains From Incomplete Data, Adrian Nachman, Alexandru Tamasan, Alexandre Timonov
Reconstruction Of Planar Conductivities In Subdomains From Incomplete Data, Adrian Nachman, Alexandru Tamasan, Alexandre Timonov
Faculty Bibliography 2010s
We consider the problem of recovering a sufficiently smooth isotropic conductivity from interior knowledge of the magnitude of the current density field vertical bar J vertical bar generated by an imposed voltage potential f on the boundary. In any dimension n > = 2, we show that equipotential sets are global area minimizers in the conformal metric determined by vertical bar J vertical bar. In two dimensions, assuming the boundary voltage is almost two-to-one, we prove uniqueness of the minimization problem. This yields two results on reconstruction from incomplete data. In the first case, vertical bar J vertical bar is known …
Triple-Junction Contribution To Diffusion In Nanocrystalline Si, A. Portavoce, L. Chow, J. Bernardini
Triple-Junction Contribution To Diffusion In Nanocrystalline Si, A. Portavoce, L. Chow, J. Bernardini
Faculty Bibliography 2010s
The influence of triple-junctions on experimental Ge diffusion profiles (850-1000 degrees C) in nanocrystalline Si is investigated using three-dimensional finite element simulations. We found that triple-junction diffusion is not negligible in nanocrystalline Si made of 40 nm wide grains. Ge triple-junction diffusion coefficient follows the Arrhenius law 5.72x10(4) exp(-3.24 eV/kT)cm(2) s(-1). It is approximately 4.7x10(2) times higher than grain boundary diffusion coefficient, even though diffusion in triple-junction and in grain boundary exhibits similar activation energy.
Prospects Of Emerging Polymer-Stabilized Blue-Phase Liquid-Crystal Displays, Linghui Rao, Jin Yan, Shin-Tson Wu
Prospects Of Emerging Polymer-Stabilized Blue-Phase Liquid-Crystal Displays, Linghui Rao, Jin Yan, Shin-Tson Wu
Faculty Bibliography 2010s
The prospects of emerging polymer-stabilized blue-phase liquid-crystal displays, or more generally, Kerr-effect-induced isotropic-to-anisotropic transition, are analyzed with special emphases on the temperature effects. As the temperature increases, both the Kerr constant, induced birefringence, and response time decrease but at different rates. The proposed physical models fit well with experimental results. Some remaining technical challenges associated with this promising display technology are discussed.
Photonic Circuits For Generating Modal, Spectral, And Polarization Entanglement, Mohammed F. Saleh, Giovanni Di Giuseppe, Bahaa E. A. Saleh, Malvin Carl Teich
Photonic Circuits For Generating Modal, Spectral, And Polarization Entanglement, Mohammed F. Saleh, Giovanni Di Giuseppe, Bahaa E. A. Saleh, Malvin Carl Teich
Faculty Bibliography 2010s
We consider the design of photonic circuits that make use of Ti:LiNbO(3) diffused channel waveguides to generate photons with various combinations of modal, spectral, and polarization entanglement. Down-converted photon pairs are generated via spontaneous parametric down-conversion (SPDC) in a two-mode waveguide (TMW). We study a class of photonic circuits comprising: 1) a nonlinear periodically poled TMW structure; 2) a set of single-mode waveguide (SMW)- and TMW-based couplers arranged in such a way that they suitably separate the three photons comprising the SPDC process; and, for some applications, 3) a holographic Bragg grating that acts as a dichroic reflector. The first …
High Quality Solution Processed Carbon Nanotube Transistors Assembled By Dielectrophoresis, Paul Stokes, Saiful I. Khondaker
High Quality Solution Processed Carbon Nanotube Transistors Assembled By Dielectrophoresis, Paul Stokes, Saiful I. Khondaker
Faculty Bibliography 2010s
We report on high quality individual solution processed single-walled carbon nanotube (SWNT) field effect transistors assembled from a commercial surfactant free solution via dielectrophoresis. The devices show field effect mobilities up to 1380 cm(2)/V s and on-state conductance up to 6 mu S. The mobility values are an order of magnitude improvement over previous solution processed SWNT devices and close to the theoretical limit. These results demonstrate that high quality SWNT devices can be obtained from solution processing and will have significant impact in high yield fabrication of SWNT nanoelectronic devices.
Directed Assembly Of Solution Processed Single-Walled Carbon Nanotubes Via Dielectrophoresis: From Aligned Array To Individual Nanotube Devices, Paul Stokes, Saiful I. Khondaker
Directed Assembly Of Solution Processed Single-Walled Carbon Nanotubes Via Dielectrophoresis: From Aligned Array To Individual Nanotube Devices, Paul Stokes, Saiful I. Khondaker
Faculty Bibliography 2010s
The authors demonstrate directed assembly of high quality solution processed single-walled carbon nanotube (SWNT) devices via ac dielectrophoresis using commercially available SWNT solutions. By controlling the shape of the electrodes, concentration of the solution, and assembly time, the authors are able to control the assembly of SWNTs from dense arrays down to individual SWNT devices. Electronic transport studies of individual SWNT devices show field effect mobilities of up to 1380 cm(2)/V s for semiconducting SWNTs and saturation currents of up to similar to 15 mu A for metallic SWNTs. The field effect mobilities are more than an order of magnitude …
Design, Implementation, And Testing Of A Cryogenic Loading Capability On An Engineering Neutron Diffractometer, T. R. Woodruff, V. B. Krishnan, B. Clausen, T. Sisneros, V. Livescu, D. W. Brown, M. A. M. Bourke, R. Vaidyanathan
Design, Implementation, And Testing Of A Cryogenic Loading Capability On An Engineering Neutron Diffractometer, T. R. Woodruff, V. B. Krishnan, B. Clausen, T. Sisneros, V. Livescu, D. W. Brown, M. A. M. Bourke, R. Vaidyanathan
Faculty Bibliography 2010s
A novel capability was designed, implemented, and tested for in situ neutron diffraction measurements during loading at cryogenic temperatures on the spectrometer for materials research at temperature and stress at Los Alamos National Laboratory. This capability allowed for the application of dynamic compressive forces of up to 250 kN on standard samples controlled at temperatures between 300 and 90 K. The approach comprised of cooling thermally isolated compression platens that in turn conductively cooled the sample in an aluminum vacuum chamber which was nominally transparent to the incident and diffracted neutrons. The cooling/heat rate and final temperature were controlled by …
Determining Time Resolution Of Microchannel Plate Detectors For Electron Time-Of-Flight Spectrometers, Qi Zhang, Kun Zhao, Zenghu Chang
Determining Time Resolution Of Microchannel Plate Detectors For Electron Time-Of-Flight Spectrometers, Qi Zhang, Kun Zhao, Zenghu Chang
Faculty Bibliography 2010s
The temporal resolution of a 40 mm diameter chevron microchannel plate (MCP) detector followed by a constant fraction discriminator and a time-to-digital converter was determined by using the third order harmonic of 25 fs Ti:sapphire laser pulses. The resolution was found to deteriorate from 200 to 300 ps as the total voltage applied on the two MCPs increased from 1600 to 2000 V. This was likely due to a partial saturation of the MCP and/or the constant fraction discriminator working with signals beyond its optimum range of pulse width and shape.
Birefringent Properties Of Cyclic Block Copolymers And Low-Retardation-Film Development, Weijun Zhou, Charles Diehl, Dan Murray, Kurt A. Koppi, Stephen Hahn, Shin-Tson Wu
Birefringent Properties Of Cyclic Block Copolymers And Low-Retardation-Film Development, Weijun Zhou, Charles Diehl, Dan Murray, Kurt A. Koppi, Stephen Hahn, Shin-Tson Wu
Faculty Bibliography 2010s
Cyclic block copolymers (CBCs) are a new class of optical polymers made by fully hydrogenating block copolymers of styrene and conjugated diene. This class of materials has excellent optical transparency, photostability, and good thermal resistance. By changing the copolymer composition and the resulting block-copolymer morphology, a unique set of birefringence properties can be achieved. The focus of this work was to study various sources of birefringence in block copolymers using a series of model CBC materials. One particularly interesting finding relates to the development of an ultra-low-phase-retardation CBC film. Unlike the conventional approach of using an additive or blend, a …