Focus and Alignment Tolerance in a Photoconductive Terahertz Source

  • Gaudencio Paz-Martínez
  • Jesus Garduño-Mejía
  • Oleg V. Kolokoltsev
  • Carlos G. Treviño-Palacios
  • Naser QureshiEmail author


Robust coupling between a pulsed laser beam and a photoelectric circuit is an important issue in the development of miniaturized, integrated, and embedded terahertz instrumentation. Here, we present a study of the effect of varying the focus and alignment parameters of an excitation laser pulse on the emission characteristics of a standard Hertzian-dipole type terahertz photoelectric source. The objective is to quantify the tolerance of a terahertz time-domain spectroscopy system, and we study the variation of peak amplitude, waveform, phase, and energy distribution as a function of excitation position and defocus. We find that a terahertz source can be made relatively tolerant to variations in focus, alignment, and details of the geometry of the photoelectric system, providing a window for a more robust field operation.


Photoconductive switch Terahertz imaging Terahertz source Terahertz spectroscopy 



This work was supported by grants PAPIIT IN104513 and IG100615 from Universidad Nacional Autónoma de México.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Gaudencio Paz-Martínez
    • 1
  • Jesus Garduño-Mejía
    • 1
  • Oleg V. Kolokoltsev
    • 1
  • Carlos G. Treviño-Palacios
    • 2
  • Naser Qureshi
    • 1
    Email author
  1. 1.Centro de Ciencias Aplicadas y Desarrollo Tecnológico (CCADET)Universidad Nacional Autónoma de MéxicoMexicoMexico
  2. 2.Instituto Nacional de Astrofísica, Optica y Electrónica(INAOE)TonanztintlaMexico

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