Fang, Yuman; Gou, Yongsheng; Zhang, Minrui; Wang, Junfeng; Tian, Jinshou

Gate modules based on avalanche technology for photocathode gating to proximity-focused microchannel-plate image intensifier (MCPII) are often limited to short gate exposures. A nanosecond pulse module based on MOSFET devices has been demonstrated at our lab, which is capable of generating pulses of adjustable full width at half maximum (FWHM) from 3 ns to D.C. operation with 1 ns switching time and a burst repetition rate up to 4 MHz. A method of supplying gate-current pulses to the MOSFET device is adopted to increase the switching speed based on the totem pole driver. Nanosecond optical gating time of an 18-mm proximity-focused MCPII with a metallic underlay photocathode was obtained. A MCPII with standard multi-alkali photocathode was analyzed for comparison. Moreover, a photocathode-MCP model based on the Finite Integral Technique (FIT) is developed to investigate the dependence of the gating time on the sheet resistance of the photocathode.

The result was published on NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. DOI: 10.1016/j.nima.2020.164799