(b) Frequency
response profile for the transmitted signal up to 40 GHz. Conclusions The observation of a high-frequency response in GR-FETs beyond 40 GHz has clarified the importance of power and intensity in microwave transmission. Following Momelotinib nmr a previous study in semiconductor QD THz sensing [4], a basic frequency NVP-BGJ398 characteristic has already been defined using a conventional microwave transconductance measurement [5]. Building on these findings, this experiment presents a systematic study which explored the GHz/THz detection limit of both bilayer and single-layer GR-FETs. THz irradiation experiments revealed the interplay of different photoresponse mechanisms, primarily involving nonlinearity and bolometric heating effects on the transport properties of the GR-FET device. The bilayer GR samples show a clear visible – faster and larger – photoresponse change in comparison to the monolayer sample. This is a direct result of the small apparent selleck chemical band gap that exists in the bilayer GR materials. The observation of such bolometric responses, especially at ultrahigh frequencies, is a highly prized characteristic for a variety of device applications. Additionally, the microwave
response of both the single- and bilayer GR-FET was significantly extended from previous reports by improving the wiring setup, insulation architecture, and heat dissipation of the GR-FET nanosensor. Even in the case of the GR Aurora Kinase two-terminal system, an excellent response was observed under room-temperature conditions [5]. Therefore, it
is possible to conclude that the GR strip line detector system serves as a valuable means to analyze high-frequency response measurements and that GR-FETs will work effectively as room-temperature GHz-THz sensors. Authors’ information YO is a regent professor; NA is an associate professor; AMM, TA, YI, and TO are graduate students; MK is a postdoctoral candidate; TO is a professor; and KM is an assistant professor from the Graduate School of Advanced Integrated Science at Chiba University. AN is an undergraduate student from the Chemistry Department at the University of Minnesota-Twin Cities. JPB is a professor in the Electrical Engineering Department, SUNY at Buffalo. DKF is a regent professor in the Department of Electrical Engineering, Arizona State University. KI is a professor in the Advanced Device Laboratory at the Institute of Physical and Chemical Research (RIKEN). Acknowledgements This work is supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (19054016, 19204030, and 16656007) and by the JSPS Core-to-Core Program. This work was also in part supported by the Global COE Program at Chiba University (G-03, MEXT) and promoted by the international research and educational collaboration between Chiba University and SUNY Buffalo.