Mid-infrared homodyne balanced detector for quantum light characterization

A scientific group from Florence, Italy (LENS, CNR-INO, INFN) and from ETH Zürich, Switzerland published in 2021 in Optics Express (Pub Med) and in 2022 in Advanced Photonics Research (Wiley-VCH GmbH) two articles describing quantum light characterization. Presented systems contain VIGO photonics products.

Large-scale introduction of quantum technologies, such as free-space quantum communication requires many high-quality research experiments in which reveal non-classicality in mid-infrared (MIR) light, e. g. in quantum cascade lasers (QCL) emission, requires a high-performance detection system. Researchers presented a MIR balanced detection system suitable for quantum characterization of light via homodyne detection made on 50/50 beam splitter and two HgCdTe photovoltaic  PVI-4TE-5-2×2 VIGO detectors working in the spectral range from 2.5 μm to 5.0 μm . Described system tested QCLs, chip-scale semiconductor-heterostructure devices based on intersubband transitions in quantum wells, operating in the mid-to-far infrared. Moreover, the system allows studying the intensity correlations between the different modes that occur in a three-mode harmonic QCLcomb.

We are proud, that VIGO detectors have payed such an important role in the investigation of the quantum properties on QCLs radiation which are yet unexplored.

Link to the article