toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Walther, Christoph; Scalari, Giacomo; Faist, Jerome; Beere, Harvey; Ritchie, David openurl 
  Title Low frequency terahertz quantum cascade laser operating from 1.6 to 1.8 THz Type Journal Article
  Year 2006 Publication Applied Physics Letters Abbreviated Journal (up) Appl. Phys. Lett.  
  Volume 89 Issue Pages 231121(1-3)  
  Keywords QCL, 360 uW at 1.6 THz  
  Abstract The authors report a GaAs/Al0.1Ga0.9As quantum cascade laser based on a bound-to-continuum transition optimized for low frequency operation. High tunability of the gain curve is achieved by the Stark effect and laser emission is measured between 1.6 and 1.8 THz. Pulsed mode operation up to 95 K and continuous wave operation up to 80 K are reported. The dynamical range in current is as high as 43%.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 629  
Permanent link to this record
 

 
Author Sekine, Norihiko; Hosako, Iwao openurl 
  Title Intensity modulation of terahertz quantum cascade lasers under external light injection Type Journal Article
  Year 2009 Publication Applied Physics Letters Abbreviated Journal (up) Appl. Phys. Lett.  
  Volume 95 Issue Pages 201106(1-3)  
  Keywords QCL modulation, THz, terahertz  
  Abstract We investigated the light-current characteristics of terahertz (THz) quantum cascade lasers under external light injection, which excites interband transitions in the active materials. It was found that the amount of reduction in the THz power was constant for all injection currents above threshold, and the dependence of the reduction amount on the wavelength of the external light was observed to show a resonancelike feature. The dominant intensity modulation mechanism was found to be the loss change caused by interband transitions in the active region. Further, the effective coupling efficiency plays an important role in the intensity modulation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 630  
Permanent link to this record
 

 
Author Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory doi  openurl
  Title Low noise and wide bandwidth of NbN hot-electron bolometer mixers Type Journal Article
  Year 2011 Publication Appl. Phys. Lett. Abbreviated Journal (up) Appl. Phys. Lett.  
  Volume 98 Issue Pages 033507 (1 to 3)  
  Keywords NbN HEB mixer  
  Abstract We report a record double sideband noise temperature of 600 K (5hν/kB) offered by a NbN hot-electron bolometer receiver at 2.5 THz. Allowing for standing wave effects, this value was found to be constant in the intermediate frequency range 1–7 GHz, which indicates that the mixer has an unprecedentedly large noise bandwidth in excess of 7 GHz. The insight into this is provided by gain bandwidth measurements performed at the superconducting transition. They show that the dependence of the bandwidth on the mixer length follows the model for an HEB mixer with diffusion and phonon cooling of the hot electrons.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number RPLAB @ gujma @ Serial 638  
Permanent link to this record
 

 
Author Baek, Burm; Lita, Adriana E.; Verma, Varun; Nam, Sae Woo openurl 
  Title Superconducting a-WxSi1–x nanowire single-photon detector with saturated internal quantum efficiency from visible to 1850 nm Type Journal Article
  Year 2011 Publication Applied Physics Letters Abbreviated Journal (up) Appl. Phys. Lett.  
  Volume 98 Issue 25 Pages 3  
  Keywords SNSPD  
  Abstract We have developed a single-photon detector based on superconducting amorphous tungsten–silicon alloy (a-WxSi1–x) nanowire. Our device made from a uniform a-WxSi1–x nanowire covers a practical detection area (16 μm×16 μm) and shows high sensitivity featuring a plateau of the internal quantum efficiencies, i.e., efficiencies of generating an electrical pulse per absorbed photon, over a broad wavelength and bias range. This material system for superconducting nanowire detector technology could overcome the limitations of the prevalent nanowire devices based on NbN and lead to more practical, ideal single-photon detectors having high efficiency, low noise, and high count rates.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number RPLAB @ gujma @ Serial 665  
Permanent link to this record
 

 
Author Terai, Hirotaka; Miki, Shigehito; Yamashita, Taro; Makise, Kazumasa; Wang, Zhen openurl 
  Title Demonstration of single-flux-quantum readout operation for superconducting single-photon detectors Type Journal Article
  Year 2010 Publication Applied Physics Letters Abbreviated Journal (up) Appl. Phys. Lett.  
  Volume 97 Issue 11 Pages 3  
  Keywords SSPD  
  Abstract A readout circuit using superconducting single-flux-quantum (SFQ) circuits has been developed to realize an independently addressable array of superconducting single-photon detectors (SSPDs). We tested the SFQ readout circuits by connecting with SSPDs. The error rates of readout circuits were below 10–5 for input signal amplitude of greater than 18.2 μA. Detection efficiencies (DEs) for single-photon incidents were measured both with and without the connection of a readout circuit. The observed DEs traced almost the same curves regardless of the connection of the readout circuit, except that the SSPD is likely to latch by connecting the readout circuit.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number RPLAB @ gujma @ Serial 654  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: