TY - JOUR
T1 - Detection properties of photoconductive antennas fabricated on low-temperature-grown GaAs and ErAs:GaAs at subterahertz band
AU - Zhang, Jitao
AU - Tuo, Mingguang
AU - Liang, Min
AU - Xin, Hao
N1 - Funding Information:
The authors are grateful to Dr. Hong Lu and Dr. Arthur Gossard at the University of California Santa Barbara for providing the ErAs:GaAs wafers. This work was financially supported by the NSF under Grant No. 1126572.
Publisher Copyright:
© 2020 Society of Photo-Optical Instrumentation Engineers (SPIE).
PY - 2020/6/1
Y1 - 2020/6/1
N2 - Terahertz (THz) spectroscopy with high sensitivity is essential for biological application considering the strong absorption and scattering effects therein. As the most commonly used THz detector, the photoconductive antenna's (PCA) response greatly relies on the properties of the substrate's material. THz detection properties of the PCAs fabricated on low-temperature-grown GaAs (LT-GaAs) and ErAs:GaAs superlattices were compared at the sub-THz band. The detection efficiency of the PCAs with regard to incident laser power was characterized. In addition, using the PCAs as detectors, the signal-to-noise ratio (SNR) and dynamic range (DR) of a terahertz time-domain spectroscopy were quantified. The result indicates that the PCA detector with LT-GaAs has higher efficiency than the one with ErAs:GaAs. Consequently, the corresponding THz spectrometer has better SNR and DR. This result is contrary to the previous report, in which enhanced detection efficiency was observed with ErAs:GaAs-based PCA, which is probably due to the different structures of ErAs:GaAs superlattices used in the experiment.
AB - Terahertz (THz) spectroscopy with high sensitivity is essential for biological application considering the strong absorption and scattering effects therein. As the most commonly used THz detector, the photoconductive antenna's (PCA) response greatly relies on the properties of the substrate's material. THz detection properties of the PCAs fabricated on low-temperature-grown GaAs (LT-GaAs) and ErAs:GaAs superlattices were compared at the sub-THz band. The detection efficiency of the PCAs with regard to incident laser power was characterized. In addition, using the PCAs as detectors, the signal-to-noise ratio (SNR) and dynamic range (DR) of a terahertz time-domain spectroscopy were quantified. The result indicates that the PCA detector with LT-GaAs has higher efficiency than the one with ErAs:GaAs. Consequently, the corresponding THz spectrometer has better SNR and DR. This result is contrary to the previous report, in which enhanced detection efficiency was observed with ErAs:GaAs-based PCA, which is probably due to the different structures of ErAs:GaAs superlattices used in the experiment.
KW - ErAs
KW - detection
KW - low-temperature-grown GaAs
KW - photoconductive antenna
KW - terahertz
UR - http://www.scopus.com/inward/record.url?scp=85089540500&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85089540500&partnerID=8YFLogxK
U2 - 10.1117/1.OE.59.6.061619
DO - 10.1117/1.OE.59.6.061619
M3 - Article
AN - SCOPUS:85089540500
VL - 59
JO - SPIE J
JF - SPIE J
SN - 0091-3286
IS - 6
M1 - 061619
ER -