Electrical-to-optical power conversion was performed to improve radiation detection performance. By the application of a laser pulse to an optical photo-detector, the incident power P can be converted into a (steady) output signal P' with displacement current. The dimensionless optoelectronic responsivity of the system is defined as R = P'/P. For a single detector, R = 1. The responsivity drops as the light crosses an array of detectors. N-doped silicon detectors and optical waveguide are the main device types used for power conversion. In this paper, we will show simulation results of a waveguide-based optical power converter coupled to a 1D stochastic detector and discuss a concept for an actively cooled detector module which is currently being developed at the Max Plank Institute for Extraterrestrial Physics. The detector module is installed on a Germany-built 305 m long linear accelerator (linac) und based on an idea developed by Eckhard Woelfel (Max Planck Institute for Extraterrestrial Physics).
The energy dissipated in internal resistances of semiconductors often represents much of the energy losses in low-power radiation detectors such as bolometers and Si(P,N) rectifying detectors. To prevent overloading of the sensor, the pulsed readout quantum efficiency must be limited to values close to 100 %. For natural xenon detectors, this can be achieved by operating the detector at low bias currents. For bolometers operating at high ambient temperature, however, the cooling efficiency increases at high bias currents as the bolometers approach their quantum efficiency limit and a compromise must be found between detector performance and bolometer temperature. In this paper, we present a method for determining the bias point at which the pulsed quantum efficiency of a detector reaches 100 %, and the application of this method is illustrated through measurements of a bolometer prototype. Our experimental results show that the optimal bias point can be attained when the bolometer is operated as close as possible to its breakdown voltage, and in this case the bolometer’s energy resolution is degraded by only a factor of two. For lower bias voltages, the bolometer’s efficiency drop is more pronounced and the efficiency reaches 100 % at lower bias levels. d2c66b5586