Now showing items 21-40 of 1823

    • Purely wavelength- and amplitude-modulated quartz-enhanced photoacoustic spectroscopy 

      Patimisco, Pietro; Sampaolo, Angelo; Bidaux, Yves; Bismuto, Alfredo; Scott, Marshall; Jiang, James; Muller, Antoine; Faist, Jerome; Tittel, Frank K.; Spagnolo, Vincenzo (2016)
      We report here on a quartz-enhanced photoacoustic (QEPAS) sensor employing a quantum cascade laser (QCL) structure capable of operating in a pure amplitude or wavelength modulation configuration. The QCL structure is ...
    • Stability of High-Density Two-Dimensional Excitons against a Mott Transition in High Magnetic Fields Probed by Coherent Terahertz Spectroscopy 

      Zhang, Qi; Wang, Yongrui; Gao, Weilu; Long, Zhongqu; Watson, John D.; Manfra, Michael J.; Belyanin, Alexey; Kono, Junichiro (2016)
      We have performed time-resolved terahertz absorption measurements on photoexcited electron-hole pairs in undoped GaAs quantum wells in magnetic fields. We probed both unbound- and bound-carrier responses via cyclotron ...
    • Mid infrared quantum cascade laser operating in pure amplitude modulation for background-free trace gas spectroscopy 

      Bidaux, Yves; Bismuto, Alfredo; Patimisco, Pietro; Sampaolo, Angelo; Gresch, Tobias; Strubi, Gregory; Blaser, Stéphane; Tittel, Frank K.; Spagnolo, Vincenzo; Muller, Antoine; Faist, Jérôme (2016)
      We present a single mode multi-section quantum cascade laser source composed of three different sections: master oscillator, gain and phase section. Non-uniform pumping of the QCL’s gain reveals that the various laser ...
    • Adsorption and Unfolding of a Single Protein Triggers Nanoparticle Aggregation 

      Dominguez-Medina, Sergio; Kisley, Lydia; Tauzin, Lawrence J.; Hoggard, Anneli; Shuang, Bo; Indrasekara, A. Swarnapali D.S.; Chen, Sishan; Wang, Lin-Yung; Derry, Paul J.; Liopo, Anton; Zubarev, Eugene R.; Landes, Christy F.; Link, Stephan (2016)
      The response of living systems to nanoparticles is thought to depend on the protein corona, which forms shortly after exposure to physiological fluids and which is linked to a wide array of pathophysiologies. A mechanistic ...
    • Highly sensitive gas leak detector based on a quartz-enhanced photoacoustic SF6 sensor 

      Sampaolo, Angelo; Patimisco, Pietro; Giglio, Marilena; Chieco, Leonardo; Scamarcio, Gaetano; Tittel, Frank K.; Spagnolo, Vincenzo (2016)
      The implementation, performance validation, and testing of a gas-leak optical sensor based on mid-IR quartz-enhanced photoacoustic (QEPAS) spectroscopic technique is reported. A QEPAS sensor was integrated in a vacuum-sealed ...
    • Compact TDLAS based sensor design using interband cascade lasers for mid-IR trace gas sensing 

      Dong, Lei; Tittel, Frank K.; Li, Chunguang; Sanchez, Nancy P.; Wu, Hongpeng; Zheng, Chuantao; Yu, Yajun; Sampaolo, Angelo; Griffin, Robert J. (2016)
      Two compact TDLAS sensor systems based on different structural optical cores were developed. The two optical cores combine two recent developments, gallium antimonide (GaSb)-based ICL and a compact multipass gas cell (MPGC) ...
    • Broadband Absorption Engineering to Enhance Light Absorption in Monolayer MoS2 

      Bahauddin, Shah Mohammad; Robatjazi, Hossein; Thomann, Isabell (2016)
      Here we take a first step toward tackling the challenge of incomplete optical absorption in monolayers of transition metal dichalcogenides for conversion of photon energy, including solar, into other forms of energy. We ...
    • Performance Analysis and Optimization of a Hybrid Seismic Imaging Application 

      Paul, Sri Raj; Araya-Polo, Mauricio; Mellor-Crummey, John; Hohl, Detlef (2016)
      Applications to process seismic data are computationally expensive and, therefore, employ scalable parallel systems to produce timely results. Here we describe our experiences of using performance analysis tools to gain ...
    • Ultrathin AAO Membrane as a Generic Template for Sub-100 nm Nanostructure Fabrication 

      Robatjazi, Hossein; Bahauddin, Shah Mohammad; Macfarlan, Luke H.; Fu, Sidan; Thomann, Isabell (2016)
      Anodic aluminum oxide (AAO) templates are emerging as a platform for simple, cost-effective, high-throughput top-down nanofabrication of regular arrays of nanostructures. Thus far, however, AAO pattern transfer has largely ...
    • Photoinduced force mapping of plasmonic nanostructures 

      Tumkur, Thejaswi U.; Yang, Xiao; Cerjan, Benjamin; Halas, Naomi J.; Nordlander, Peter; Thomann, Isabell (2016)
      The ability to image the optical near-fields of nanoscale structures, map their morphology and concurrently obtain spectroscopic information, all with high spatiotemporal resolution, is a highly sought-after technique in ...
    • Analysis of overtone flexural modes operation in quartz-enhanced photoacoustic spectroscopy 

      Tittel, Frank K.; Sampaolo, Angelo; Patimisco, Pietro; Dong, Lei; Geras, Antonina; Starecki, Tomasz; Spagnolo, Vincenzo (2016)
      A detailed investigation of a set of custom quartz tuning forks (QTFs), operating in the fundamental and first overtone flexural modes is reported. Support losses are the dominant energy dissipation processes when the QTFs ...
    • High Chromaticity Aluminum Plasmonic Pixels for Active Liquid Crystal Displays 

      Olson, Jana; Manjavacas, Alejandro; Basu, Tiyash; Huang, Da; Schlather, Andrea E.; Zheng, Bob; Halas, Naomi; Nordlander, Peter; Link, Stephan (2016)
      Chromatic devices such as flat panel displays could, in principle, be substantially improved by incorporating aluminum plasmonic nanostructures instead of conventional chromophores that are susceptible to photobleaching. ...
    • Improved Tuning Fork for Terahertz Quartz-Enhanced Photoacoustic Spectroscopy 

      Sampaolo, Angelo; Patimisco, Pietro; Giglio, Marilena; Vitiello, Miriam S.; Beere, Harvey E.; Ritchie, David A.; Scamarcio, Gaetano; Tittel, Frank K.; Spagnolo, Vincenzo (2016)
      We report on a quartz-enhanced photoacoustic (QEPAS) sensor for methanol (CH₃OH) detection employing a novel quartz tuning fork (QTF), specifically designed to enhance the QEPAS sensing performance in the terahertz (THz) ...
    • Chiral and Achiral Nanodumbbell Dimers: The Effect of Geometry on Plasmonic Properties 

      Smith, Kyle W.; Zhao, Hangqi; Zhang, Hui; Sánchez -Iglesias, Ana; Grzelczak, Marek; Wang, Yumin; Chang, Wei-Shun; Nordlander, Peter; Liz-Marzán, Luis; Link, Stephan (2016)
      Metal nanoparticles with a dumbbell-like geometry have plasmonic properties similar to those of their nanorod counterparts, but the unique steric constraints induced by their enlarged tips result in distinct geometries ...
    • Dicke superradiance in solids [Invited] 

      Cong, Kankan; Zhang, Qi; Wang, Yongrui; Noe, G. Timothy; Belyanin, Alexey; Kono, Junichiro (2016)
      Recent advances in optical studies of condensed matter systems have led to the emergence of a variety of phenomena that have conventionally been studied in the realm of quantum optics. These studies have not only deepened ...
    • Mid-infrared dual-gas sensor for simultaneous detection of methane and ethane using a single continuous-wave interband cascade laser 

      Ye, Weilin; Li, Chunguang; Zheng, Chuantao; Sanchez, Nancy P.; Gluszek, Aleksander K.; Hudzikowski, Arkadiusz J.; Dong, Lei; Griffin, Robert J.; Tittel, Frank K. (2016)
      A continuous-wave (CW) interband cascade laser (ICL) based mid-infrared sensor system was demonstrated for simultaneous detection of atmospheric methane (CH4) and ethane (C2H6). A 3.337 µm CW ICL with an emitting wavenumber ...
    • Wafer-scale monodomain films of spontaneously aligned single-walled carbon nanotubes 

      He, Xiaowei; Gao, Weilu; Xie, Lijuan; Li, Bo; Zhang, Qi; Lei, Sidong; Robinson, John M.; Hároz, Erik H.; Doorn, Stephen K.; Wang, Weipeng; Vajtai, Robert; Ajayan, Pulickel M.; Adams, W. Wade; Hauge, Robert H.; Kono, Junichiro (2016)
      The one-dimensional character of electrons, phonons and excitons in individual single-walled carbon nanotubes leads to extremely anisotropic electronic, thermal and optical properties. However, despite significant efforts ...
    • Deep imaging in scattering media with selective plane illumination microscopy 

      Pediredla, Adithya Kumar; Zhang, Shizheng; Avants, Ben; Ye, Fan; Nagayama, Shin; Chen, Ziying; Kemere, Caleb; Robinson, Jacob T.; Veeraraghavan, Ashok (2016)
      In most biological tissues, light scattering due to small differences in refractive index limits the depth of optical imaging systems. Two-photon microscopy (2PM), which significantly reduces the scattering of the excitation ...
    • Universal microbial diagnostics using random DNA probes 

      Aghazadeh, Amirali; Lin, Adam Y.; Sheikh, Mona A.; Chen, Allen L.; Atkins, Lisa M.; Johnson, Coreen L.; Petrosino, Joseph F.; Drezek, Rebekah A.; Baraniuk, Richard G. (2016)
      Early identification of pathogens is essential for limiting development of therapy-resistant pathogens and mitigating infectious disease outbreaks. Most bacterial detection schemes use target-specific probes to differentiate ...
    • Measuring Competence in Metered Dose Inhaler Use Using Capmedic Electronic Inhaler MonitoringᅠTool 

      Biswas, Rajoshi; Patel, Gaurav; Mohsin, Ali; Hanania, Nicola A.; Sabharwal, Ashutosh (2016)
      It is estimated that up to 70-90% of asthma and COPD patients use their Metered Dose Inhalers (MDIs) incorrectly. However, clinicians often fail to detect patients’ incorrect MDI technique by observation alone. In this ...