Quantum cascade lasers

Quantum cascade lasers are made up of many thin layers of semiconductor. An injected electron makes a small energy transition as it moves from one layer to the next, emitting light on each cascade. Because the energy steps are small, quantum cascade lasers can produce long-wavelength mid-infrared or terahertz radiation.

Latest Research and Reviews

  • Research
    | Open Access

    Photonic solutions for generating free space millimeter radiation is a fast developing field that combines optoelectronics and RF domains but has many challenges. Here the authors present a quantum cascade laser (QCL) based solution for THz laser emission and millimeter wave generation in a single device.

    • Valentino Pistore
    • , Hanond Nong
    •  & Sukhdeep S. Dhillon
  • Research
    | Open Access

    Broadband integrated electrical modulators are key components for photonic systems. Here, the authors present a room temperature mid-IR free-space amplitude modulator based on a semiconductor heterostructure that exploits the change in reflectance occurring at the change between weak and strong coupling.

    • Stefano Pirotta
    • , Ngoc-Linh Tran
    •  & Raffaele Colombelli
  • Research
    | Open Access

    Tunable quantum cascade lasers can enable applications in multiple areas. Here, the authors demonstrate the adaptive control of the modes and emission spectra of quantum cascade random lasers through a spatially-tailored optical modulation of the active region.

    • S. Schönhuber
    • , N. Bachelard
    •  & K. Unterrainer
  • Research
    | Open Access

    Structures that can enhance the capabilities of quantum cascade lasers are highly sought after to improve their practicality for a range of applications. Here the authors demonstrate such a structure in a saturable absorber that takes advantage of intersubband polaritons in the terahertz range and study coherent nonlinear dynamics in the system.

    • Jürgen Raab
    • , Francesco P. Mezzapesa
    •  & Miriam S. Vitiello
  • Research
    | Open Access

    THz dual comb spectroscopy may be performed using down-converted or quantum cascade laser systems, forcing a choice between absolute frequency referencing and high sensitivity. Here, these strengths are combined in a hybrid, dual frequency comb spectrometer, capable of high-accuracy measurements on molecular transitions.

    • Luigi Consolino
    • , Malik Nafa
    •  & Paolo De Natale

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