Flat response detectors for the vacuum ultraviolet and soft x‐ray region: InP:Fe photoconductors

We have demonstrated that InP:Fe photoconductive detectors are sensitive to radiation between 20 and 3000 eV. Within experimental error the measured response is flat in this energy range, in agreement with theory. This property, coupled with the simplicity and high speed (full width at one half maximum of less than 200 ps) of these devices, makes them very interesting for the measurement of pulsed vacuum ultraviolet and x‐ray radiation and the total instantaneous integrated radiative power emitted from a pulsed source. Low fidelity response can occur in these devices for excitation times that are many times longer than the primary response time of the detector.