Up to now, the only photocathode material available for streak measurements at > 1000 nm has been the so-called S-1 material. S-1 material features excellent temporal resolution of better than 1 ps, but suffers from low quantum efficiencies at longer wavelengths. After many years of development, Hamamatsu Photonics is now, for the first time, making commercially available a streak photocathode made of InP/InGaAs. This photocathode has a sensitivity several orders of magnitude higher than S-1, and also extends its range up to 1650 nm, where S-1 is unsuitable.
A crucial characteristic of all IR detectors is their dark current. In order to suppress the dark current, and thereby make the device suitable for low-light-level applications, the photocathode operates at a working temperature of approximately -100 °C by means of liquid nitrogen cooling.
The time resolution of the C11293 is better than 20 ps FWHM. It can run at arbitrary repetition rates up to a maximum of 20 MHz, making it very versatile and easy to combine with many experimental setups.
The C11293 is suited to a wide range of application areas including time-resolved spectroscopy in semiconductor physics, quantum dots, carbon nanotubes and other nanostructure research, photovoltaic research, photonics crystals, and many others.