A multichannel calorimeter system is designed and constructed which is capable of delivering single-shot and broad-band spectral measurement of Terahertz radiation generated in intense laser-plasma interactions. The generation mechanism of backward THz radiation is studied using the multichannel calorimeter system in an intense picosecond laser-solid interaction experiment. The dependence of the BTR energy and spectrum on laser energy, target thickness and pre-plasma scale length is obtained. These results indicate that coherent transition radiation is responsible for the low frequency component (< 1 THz) of BTR. It is also observed that a largescale pre-plasma primarily enhance the high frequency component (> 3 THz) of BTR.
Liu Hao, Liao Guo-Qian, Zhang Yihang, Zhu Bao-Jun, Zhang Zhe, Li Yutong, Scott Graeme, Rusby Dean, Armstrong Chris, Zemaityte Egle, Bradford Philip, Woolsey Nigel, Huggard Peter, McKenna Paul, Neely David. Study of backward terahertz radiation from intense picosecond laser-solid interactions using a multichannel calorimeter system[J]. High Power Laser Science and Engineering, , (): .
