Now showing items 21-40 of 1769

    • 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 ...
    • Stargazin Modulation of AMPA Receptors 

      Shaikh, Sana A.; Dolino, Drew M.; Lee, Garam; Chatterjee, Sudeshna; MacLean, David M.; Flatebo, Charlotte; Landes, Christy F.; Jayaraman, Vasanthi (2016)
      Fast excitatory synaptic signaling in the mammalian brain is mediated by AMPA-type ionotropic glutamate receptors. In neurons, AMPA receptors co-assemble with auxiliary proteins, such as stargazin, which can markedly alter ...
    • 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 ...
    • 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 ...
    • 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 ...
    • 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 ...
    • A Probabilistic Framework for Deep Learning 

      Patel, Ankit B.; Nguyen, Tan; Baraniuk, Richard G. (2016)
      We develop a probabilistic framework for deep learning based on the Deep Rendering Mixture Model (DRMM), a new generative probabilistic model that explicitly capture variations in data due to latent task nuisance variables. ...
    • 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 ...
    • Inference by Reparameterization using Neural Population Codes 

      Vasudeva Raju, Rajkumar (2015-12-04)
      Behavioral experiments on humans and animals suggest that the brain performs probabilistic inference to interpret its environment. Here we present a general-purpose, biologically plausible implementation of approximate ...
    • Evaluating Multihop Mobile Wireless Networks with Controllable Node Sparsity or Density 

      Amiri, Keyvan (2015-12-04)
      Simulation is the most widely used tool for evaluating the performance of multihop mobile wireless networks, yet such simulation has so far been limited due to the lack of sufficient wireless mobility models for creating ...
    • Full-duplex Wireless with Large Antenna Arrays 

      Everett, Evan Jackson (2015-12-03)
      To meet the growing demand for wireless data, base stations with very large antenna arrays are being deployed in order to serve multiple users simultaneously. Concurrently, there is growing interest in full-duplex operation. ...
    • Rethinking Image Compression for the Object Detection Task 

      Barua, Souptik (2015-12-03)
      Traditionally, image compression algorithms, such as JPEG, have been designed for human viewers' satisfaction. Increasingly however, more and more images are being viewed by computers, for performing computer vision tasks ...
    • MIMO Broadcast Channels with Full-duplex feedback 

      Du, Xu (2015-12-03)
      In this thesis, I utilize full-duplex radios to increase the downlink spectral efficiency of MIMO broadcast channels by proposing a sequential beamforming strategy. In current half-duplex multiuser MIMO systems, non-trivial ...
    • Nonlinear neural codes 

      Yang, Qianli (2015-12-03)
      Most natural task-relevant variables are encoded in the early sensory cortex in a form that can only be decoded nonlinearly. Yet despite being a core function of the brain, nonlinear population codes are rarely studied and ...
    • A Resource-Aware Streaming-based Framework for Big Data Analysis 

      Darvish Rouhani, Bita (2015-12-02)
      The ever growing body of digital data is challenging conventional analytical techniques in machine learning, computer vision, and signal processing. Traditional analytical methods have been mainly developed based on the ...
    • GPU Accelerated Reconfigurable Detector and Precoder for Massive MIMO SDR Systems 

      Li, Kaipeng (2015-12-02)
      We present a reconfigurable GPU-based unified detector and precoder for massive MIMO software-defined radio systems. To enable high throughput, we implement the linear minimum mean square error detector/precoder and further ...
    • Wafer-scale films of aligned single-wall carbon nanotubes: preparation, characterization, and optoelectronic applications 

      He, Xiaowei (2015-11-20)
      Single-wall carbon nanotubes (SWCNTs) are one-dimensional materials defined by a cylindrical and hollow structure with aspect ratios of up to 10^7:1. Individual SWCNTs have been shown to possess excellent electric, optical, ...
    • Methods for Ripple Detection and Spike Sorting During Hippocampal Replay 

      Sethi, Ankit (2015-09-21)
      In the rat hippocampus, fast oscillations termed sharp wave ripples and an associated sequential firing of neurons, termed replay, have been identified as playing a crucial role in memory formation and learning. The term ...
    • Imaging and Visual Classification by Knowledge-Enhanced Compressive Imaging 

      Li, Yun (2015-09-10)
      Compressive imaging is a technology that uses multiplexed measurements and the sparsity of many natural images to efficiently capture and reconstruct images. The compressive single pixel camera is one embodiment of such ...
    • Molecular Plasmonics: Graphene Plasmons in the Picoscale Limit 

      Lauchner, Adam (2015-08-20)
      Doped graphene supports surface plasmons in the mid- to far-infrared that are both electrically and spatially tunable. Graphene has been shown to enable greater spatial confinement of the plasmon and fewer losses than ...