Based on the hot electron effect in a semiconductor, an overmoded resistive sensor for 0.3-0.4 THz band is investi-gated. The distribution of electromagnetic field components, voltage standing wave ratio （VSWR）, and...Based on the hot electron effect in a semiconductor, an overmoded resistive sensor for 0.3-0.4 THz band is investi-gated. The distribution of electromagnetic field components, voltage standing wave ratio （VSWR）, and the average electric field in the silicon block are obtained by using the three-dimensional finite-difference time-domain （FDTD） method. By adjusting several factors （such as the length, width, height and specific resistance of the silicon block） a novel sensor with optimal structural parameters that can be used as a power measurement device for high power terahertz pulse directly is proposed. The results show that the sensor has a relative sensitivity of about 0.24 kW 1, with a fluctuation of relative sensitivity of no more than ±22%, and the maximum of VSWR is 2.74 for 0.3-0.4 THz band.展开更多
The Compact Pulsed Hadron Source （CPHS） project is a university-based proton accelerator platform （13 MeV,16 kW,50 mA peak current,0.5 ms pulse width at 50 Hz） for multi-disciplinary neutron and proton application...The Compact Pulsed Hadron Source （CPHS） project is a university-based proton accelerator platform （13 MeV,16 kW,50 mA peak current,0.5 ms pulse width at 50 Hz） for multi-disciplinary neutron and proton applications.The CPHS linac consists of a 3 MeV radio-frequency quadrupole （RFQ） linac and a 13 MeV drift tube linac （DTL）.Both the RFQ and DTL share a 325 MHz,2.1 MW klystron source.A single iris-type radio-frequency （RF） coupler is used to feed 537 kW of RF power to the RFQ cavity.Three-dimensional electromagnetic models of the ridge-loaded tapered waveguide （RLWG） and the coupler-cavity system are presented,and the design process and results of the RLWG and iris plate are described in detail.展开更多
SLAC energy doubler （SLED） type radio-frequency pulse compressors are widely used in large-scale particle accelerators for converting long-duration moderate-power input pulses into short-duration high-power output p...SLAC energy doubler （SLED） type radio-frequency pulse compressors are widely used in large-scale particle accelerators for converting long-duration moderate-power input pulses into short-duration high-power output pulses. Phase shift keying （PSK） is one of the key components in SLED pulse compression systems. Performance of the PSK will influence the output characteristics of the SLED, such as the rise-time of the output pulse, maximal peak power gain, and energy efficiency. In this paper, a high power microwave source based on power combining and pulse compression of conventional klystrons is introduced. The effects of nonideal PSK with slow switching speed and PSK without power output during the switching process are investigated, and the experimental results with nonideal PSK agree well with the analytical results.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61231003)
文摘Based on the hot electron effect in a semiconductor, an overmoded resistive sensor for 0.3-0.4 THz band is investi-gated. The distribution of electromagnetic field components, voltage standing wave ratio （VSWR）, and the average electric field in the silicon block are obtained by using the three-dimensional finite-difference time-domain （FDTD） method. By adjusting several factors （such as the length, width, height and specific resistance of the silicon block） a novel sensor with optimal structural parameters that can be used as a power measurement device for high power terahertz pulse directly is proposed. The results show that the sensor has a relative sensitivity of about 0.24 kW 1, with a fluctuation of relative sensitivity of no more than ±22%, and the maximum of VSWR is 2.74 for 0.3-0.4 THz band.
文摘The Compact Pulsed Hadron Source （CPHS） project is a university-based proton accelerator platform （13 MeV,16 kW,50 mA peak current,0.5 ms pulse width at 50 Hz） for multi-disciplinary neutron and proton applications.The CPHS linac consists of a 3 MeV radio-frequency quadrupole （RFQ） linac and a 13 MeV drift tube linac （DTL）.Both the RFQ and DTL share a 325 MHz,2.1 MW klystron source.A single iris-type radio-frequency （RF） coupler is used to feed 537 kW of RF power to the RFQ cavity.Three-dimensional electromagnetic models of the ridge-loaded tapered waveguide （RLWG） and the coupler-cavity system are presented,and the design process and results of the RLWG and iris plate are described in detail.
文摘SLAC energy doubler （SLED） type radio-frequency pulse compressors are widely used in large-scale particle accelerators for converting long-duration moderate-power input pulses into short-duration high-power output pulses. Phase shift keying （PSK） is one of the key components in SLED pulse compression systems. Performance of the PSK will influence the output characteristics of the SLED, such as the rise-time of the output pulse, maximal peak power gain, and energy efficiency. In this paper, a high power microwave source based on power combining and pulse compression of conventional klystrons is introduced. The effects of nonideal PSK with slow switching speed and PSK without power output during the switching process are investigated, and the experimental results with nonideal PSK agree well with the analytical results.
