Abstract-Advanced non-quasi-static(NQS) compact model for characterization of non-resonant plasmonic terahertz detector

Sang Hyo Ahn, Min Woo Ryu,  Esan Jang, Hyeong Ju Jeon, Kyung Rok Kim

http://ieeexplore.ieee.org/document/8085323/

We propose advanced non-quasi-static (NQS) compact model of field-effect transistor (FET) for the characterization of a non-resonant plasma-mode terahertz (THz) detector in THz frequency regime by verifying the gate resistance effects on the transient delay and non-resonant plasmonic mechanism with characteristic length, which is a propagation distance of 2-dimensional electron gas (l2DEG), in the channel. Under the super-imposed small-signal ac voltage with 0.2 THz frequency in HSPICE simulation, the plasmonic THz power detection simulation capability of the proposed NQS model has been verified by demonstrating the well-matched results of dc output voltage (Δu) with calibrated TCAD and experimentally measured data. These results can provide the reliable circuit simulation platform for real-time multi-pixel THz imaging operation

Abstract-Highly-sensitive plasmonic nano-ring transistor for monolithic terahertz active antenna

 Min Woo Ryu,  Ramesh Patel,  Esan Jang, Sang Hyo Ahn, Hyeong Ju Jeon, Mun Seok Choe, Eunmi Choi,  Ki Jin Han,  Kyung Rok Kim

http://ieeexplore.ieee.org/document/8117385/

We report a highly-sensitive plasmonic nano-ring transistor for monolithic terahertz (THz) active antenna. By designing an ultimate asymmetric transistor on a metal-gate structure, more enhanced (180 times) channel charge asymmetry has been obtained in comparison with a bar-type asymmetric transistor of our previous work. In addition, by exploiting ring-type transistor itself as a monolithic circular active antenna, which is designed for a 0.12-THz resonance frequency, we experimentally demonstrated the highly-enhanced responsivity (RV) > 1 kV/W (× 5) and reduced noise-equivalent power (NEP) <; 10 pW/Hz0.5 (× 1/10).

Abstract-Highly-Sensitive Thin Film THz Detector Based on Edge Metal-Semiconductor-Metal Junction

Youngeun Jeon, Sungchul Jung, Hanbyul Jin, Kyuhyung Mo, Kyung Rok Kim, Wook-Ki Park, Seong-Tae Han,  Kibog Park

https://www.nature.com/articles/s41598-017-16923-z?WT.feed_name=subjects_scientific-community-and-society

Terahertz (THz) detectors have been extensively studied for various applications such as security, wireless communication, and medical imaging. In case of metal-insulator-metal (MIM) tunnel junction THz detector, a small junction area is desirable because the detector response time can be shortened by reducing it. An edge metal-semiconductor-metal (EMSM) junction has been developed with a small junction area controlled precisely by the thicknesses of metal and semiconductor films. The voltage response of the EMSM THz detector shows the clear dependence on the polarization angle of incident THz wave and the responsivity is found to be very high (~2,169 V/W) at 0.4 THz without any antenna and signal amplifier. The EMSM junction structure can be a new and efficient way of fabricating the nonlinear device THz detector with high cut-off frequency relying on extremely small junction area.