Room-Temperature Response Performance of Coupled Doped-Well Quantum Cascade Detectors with Array Structure

Energy level interaction and electron concentration are crucial aspects that affect the response performance of quantum cascade detectors (QCDs). In this work, two different-structured array QCDs are prepared, and the detectivity reaches 10(9) cm center dot Hz(1/2)/W at room temperature. The overlap integral (OI) and oscillator strength (OS) between different energy levels under a series of applied biases are fitted and reveal the influence of energy level interaction on the response performance. The redistribution of electrons in the cascade structure at room temperatures is established. The coupled doped-well structure shows a higher electron concentration at room temperature, which represents a high absorption efficiency in the active region. Even better responsivity and detectivity are exhibited in the coupled doped-well QCD. These results offer a novel strategy to understand the mechanisms that affect response performance and expand the application range of QCDs for long-wave infrared (LWIR) detection.

Automated summary

In this study, two different-structured quantum cascade detectors (QCDs) were prepared, and the detectivity reached 10(9) cm center dot Hz(1/2)/W at room temperature. By fitting the overlap integral (OI) and oscillator strength (OS) between different energy levels under a series of applied biases, the influence of energy level interaction on the response performance was revealed. The redistribution of electrons in the cascade structure at room temperatures was established. The coupled doped-well QCD showed even better responsivity and detectivity, providing a novel strategy to understand the mechanisms that affect response performance and expand the application range of QCDs for long-wave infrared (LWIR) detection.