Oscillation effect in frequency domain current from a photoconductive antenna via double-probe-pulse terahertz detection technique
Abstract
Via constructing a special terahertz time domain spectroscopy (THz-TDS) system in which two femtosecond (fs) laser pulses were used as probe pulses to excite a photoconductive (PC) THz detector, the time behavior of the current from the detector was measured. The corresponding theoretical analysis was performed by a well-known equivalent-circuit model. When the time domain current was transformed to frequency domain, an oscillation effect was observed. The oscillation frequency was decided by the time delay between the two probe pulses. The number of the extrema in the frequency domain current curve was proportion to the pulse interval in 0.1–2 THz. A method to measure the interval of fs laser pulses was proposed. It is important for applications of fs laser pulses or train.
Keywords
terahertz (THz) photoconductivity frequency oscillationPreview
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References
- 1.Pedersen J E, Lyssenko V G, Hvam J M, Jepsen P U, Keiding S R, Sørensen C B, Lindelof P E. Ultrafast local field dynamics in photoconductive THz antennas. Applied Physics Letters, 1993, 62(11): 1265–1267CrossRefGoogle Scholar
- 2.Jacobsen R H, Birkelund K, Holst T, Jepsen P U, Keiding S R. Interpretation of photocurrent correlation measurements used for ultrafast photoconductive switch characterization. Journal of Applied Physics, 1996, 79(5): 2649–2657CrossRefGoogle Scholar
- 3.Jepsen P U, Jacobsen R H, Keiding S R. Generation and detection of terahertz pulses from biased semiconductor antennas. Journal of the Optical Society of America B, Optical Physics, 1996, 13(11): 2424–2436CrossRefGoogle Scholar
- 4.Yano R, Gotoh H, Hirayama Y, Miyashita S. Systematic pumpprobe terahertz wave emission spectroscopy of a photoconductive antenna fabricated on low-temperature grown GaAs. Journal of Applied Physics, 2004, 96(7): 3635–3638CrossRefGoogle Scholar
- 5.Loata G C. Investigation of low-temperature-grown GaAs photoconductive antennae for continuous-wave and pulsed terahertz generation. Dissertation for the Doctoral Degree. Frankfut am Main: Goethe-University, 2007Google Scholar
- 6.Loata G C, Löffler T, Roskos H G. Evidence for long-living charge carriers in electrically biased low-temperature-grown GaAs photoconductive switches. Applied Physics Letters, 2007, 90(5): 052101-1–052101-3CrossRefGoogle Scholar
- 7.Loata G C, Thomson M D, Löffler T, Roskos H G. Radiation field screening in photoconductive antennae studied via pulsed terahertz emission spectroscopy. Applied Physics Letters, 2007, 91(23): 232506-1–232506-3CrossRefGoogle Scholar
- 8.Siebert K J, Lisauskas A, Löffler T, Roskos H G. Field screening in low-temperature-grown GaAs photoconductive antennas. Japanese Journal of Applied Physics, 2004, 43(3R): 1038–1043CrossRefGoogle Scholar
- 9.Darrow J T, Zhang X, Auston D H, Morse J D. Saturation properties of large-aperture photoconducting antennas. IEEE Journal of Quantum Electronics, 1992, 28(6): 1607–1616CrossRefGoogle Scholar
- 10.Liu J, Zou S, Yang Z, Wang K, Ye K. Wave shape recovery for terahertz pulse field detection via photoconductive antenna. Optics Letters, 2013, 38(13): 2268–2270CrossRefGoogle Scholar
- 11.Kim D S, Citrin D S. Coulomb and radiation screening in photoconductive terahertz sources. Applied Physics Letters, 2006, 88(16): 161117-1–161117-3Google Scholar
- 12.Zhang X, Xu J. Introduction to THz Wave Photonics. New York: Springer, 2010, Chap. 2CrossRefGoogle Scholar