To accommodate variable terahertz application situations, a compact, high-sensitivity and room-temperature terahertz detection module is designed and demonstrated. The detection module with a volume of less than 350 cm3 integrates a quasi-optically coupled terahertz detector, complementary-metal-oxide-semiconductor-based (CMOS-based) voltage amplifier circuit and bias circuit. An antenna-coupled AlGaN/GaN high-electron-mobility transistor (HEMT) are designed to detect terahertz waves by using self-mixing mechanism. The electrical signal from the detector chip is amplified by a voltage amplifier circuit. The amplifier circuit’s voltage gain can be adjusted from 100 to 700 to accommodate different requirements. The bias circuit provides bias voltage to the gate of the detector. Ability to detect both continuous and pulsed terahertz waves by the module is demonstrated. Under a coherent continuous terahertz irradiation from 0.73 to 1.13 THz, an average noise-equivalent power (NEP) of 23.6 pW/ √ Hz, a maximum optical responsivity of 1281 V/W (w/o Gain) and a minimum NEP of 15.3 pW/ √ Hz are achieved. Under a 4.3 THz pulsed radiation from quantum cascade laser (QCL), the module has a peak optical responsivity of 26 V/W (with Gain = 700) and a NEP of 567 nW/ √ Hz. The rise time of the output signal is 1.14 μs and the fall time is 0.78 μs when the module is operated at a maximum amplification gain of 700 and 6 kHz modulation frequency. To further enhance the sensitivity of the detection module, the design of the detector and the noise of the circuit need to be considered.
Monolithically integration of III-V compounds on Si (100) substrates has gained extensive interest due to its great potential in silicon photonics. However, it is greatly challenging to grow InGaAs on Si (100) because of massive defects arise in result of large lattice mismatch. In this paper, In0.53GaAs on GaP/Si (100) substrates by applying InxGa1-xAs/InP superlattices (SLs) dislocation filter layers were grown by solid-state molecular beam epitaxy (SSMBE). High-resolution X-ray diffraction (HRXRD), atomic force microscopy (AFM), cross-sectional transmission electron microscopy (TEM), and energy dispersive spectrometer (EDS) mapping were used to investigate the defect formation and evolution in epitaxial layers. Three different types of defects were found on the surface. Defect formation was directly linked to different growth stages, in which oval defect was attributed to over desorption during the initial substrate treatment, and irregular defect was originated from the region between GaP islands in GaP buffer layer, while “pair” defect was constructed by stacking faults generated in the dislocation filter layers.
Localized plasmon modes are excited and probed in a large-area grating-gate GaN/AlGaN high-electron-mobility transistor structure embedded in a Fabry-Pérot cavity using a terahertz time-domain spectroscopy (THz-TDS) at cryogenic temperature. Determined by the length of grating finger and the electron concentration, the frequency of localized plasmon modes can be continuously tuned by the gate voltage in the spectral range from 0.1 THz to 1.5 THz. When the plasmon frequency is tuned to be in resonance with the terahertz Fabry-Pérot cavity mode, a strong coupling between the plasmon mode and the cavity mode is observed and the terahertz plasmon-polaritons are formed in such a cavity-coupled two-dimensional electron system. The electromagnetic simulations have confirmed the strong coupling between them.
Conference Committee Involvement (7)
Infrared, Millimeter-Wave, and Terahertz Technologies XII
12 October 2025 | Beijing, China
Infrared, Millimeter-Wave, and Terahertz Technologies XI
13 October 2024 | Nantong, Jiangsu, China
Infrared, Millimeter-Wave, and Terahertz Technologies X
15 October 2023 | Beijing, China
Infrared, Millimeter-Wave, and Terahertz Technologies IX
5 December 2022 | Online Only, China
Infrared, Millimeter-Wave, and Terahertz Technologies VIII
10 October 2021 | Nantong, JS, China
Infrared, Millimeter-Wave, and Terahertz Technologies VII
12 October 2020 | Online Only, China
Infrared, Millimeter-Wave, and Terahertz Technologies VI
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.