High-speed quantum cascade detector characterized with a mid-infrared femtosecond oscillator
Abstract
Quantum cascade detectors (QCD) are photovoltaic mid-infrared detectors based on intersubband transitions. Owing to the sub-picosecond carrier transport between subbands and the absence of a bias voltage, QCDs are ideally suited for high-speed and room temperature operation. Here, we demonstrate the design, fabrication, and characterization of 4.3 µm wavelength QCDs optimized for large electrical bandwidth. The detector signal is extracted via a tapered coplanar waveguide (CPW), which was impedance-matched to 50 Ω. Using femtosecond pulses generated by a mid-infrared optical parametric oscillator (OPO), we show that the impulse response of the fully packaged QCDs has a full-width at half-maximum of only 13.4 ps corresponding to a 3-dB bandwidth of more than 20 GHz. Considerable detection capability beyond the 3-dB bandwidth is reported up to at least 50 GHz, which allows us to measure more than 600 harmonics of the OPO repetition frequency reaching 38 dB signal-to-noise ratio without the need of electronic amplification.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 08, 2021
- Source ID
- 10.1364/oe.417976
Entities
People
- Aaron Maxwell Andrews
- Benedikt Schwarz
- Gottfried Strasser
- Hedwig Knötig
- Johannes Hillbrand
- Jonas Heidrich
- Léonard Matthieu Krüger
- Sandro Dal Cin
- Ursula Keller
Organizations
- Air Force Office of Scientific Research
- Austrian Science Fund
- ETH Zurich
- European Research Council