A Graphene-Based Terahertz Hot Electron Bolometer with Johnson Noise Readout
In this paper, we present the development of a graphene-based hot electron bolometer with Johnson noise readout. The bolometer is a graphene microbridge connected to a log spiral antenna by Au contact pads. The Fourier transform spectrometer measurement shows the bolometer has high coupling efficiency in the frequency range from 0.3 to 1.6 THz. Using 300/77 K blackbody loads, we measure an optical noise equivalent power of 5.6 × 10−12 W/Hz0.5 at 3.0 K. To understand the thermal transport inside the graphene microbridge, we measure the bolometers with different microbridge lengths at different bath temperatures. We find that the thermal conductance due to electron diffusion is significant in the bolometers.
KeywordsGraphene Terahertz Hot electron bolometer Johnson noise readout Equivalent noise power
This work is supported in part by CAS under Grant No. XDB23020200, in part by NSFC under Grant Nos. 11190012 and 11473075, and in part by the CAS Joint Key Lab for Radio Astronomy.
- 6.K.C. Fong, K.C. Schwab, Phys. Rev. X 2, 031006 (2012)Google Scholar