High-responsivity operation of quantum cascade detectors at 9 µm
Georg Marschick, Mauro David, Elena Arigliani, Nikola Opačak, Benedikt Schwarz, Miriam Giparakis, Alexandre Delga, M. Lagrée, Thomas Poletti, Virginie Trinité, Axel Evirgen, Bruno Gérard, Georg Ramer, Richard Maulini, Jérémy Butet, Stéphane Blaser, A. M. Andrews, G. Strasser, Borislav Hinkov
Abstract
Quantum cascade detectors (QCDs) are devices operating at zero external bias with a low dark-current. They show linear detection and high saturation intensities, making them suitable candidates for heterodyne detection in long-wave infrared (LWIR) free space optical communication systems. We present an approach to mitigate the performance limitation at long wavelengths, by a comparison of similar single and multi-period QCDs for optimizing their responsivity and noise behaviour. Our InGaAs/InAlAs/InP ridge QCDs are designed for operation at λ = 9.124 µm. Optical waveguide simulations support the accurate optical characterization. A detailed device analysis reveals room-temperature responsivities of 111 mA/W for the 15-period and 411 mA/W for the single-period device.