Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14, Trento 38123, Italy.
DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Roskilde 4000, Denmark.
Nat Commun. 2017 May 15;8:15184. doi: 10.1038/ncomms15184.
Quantum measurements using single-photon detectors are opening interesting new perspectives in diverse fields such as remote sensing, quantum cryptography and quantum computing. A particularly demanding class of applications relies on the simultaneous detection of correlated single photons. In the visible and near infrared wavelength ranges suitable single-photon detectors do exist. However, low detector quantum efficiency or excessive noise has hampered their mid-infrared (MIR) counterpart. Fast and highly efficient single-photon detectors are thus highly sought after for MIR applications. Here we pave the way to quantum measurements in the MIR by the demonstration of a room temperature coincidence measurement with non-degenerate twin photons at about 3.1 μm. The experiment is based on the spectral translation of MIR radiation into the visible region, by means of efficient up-converter modules. The up-converted pairs are then detected with low-noise silicon avalanche photodiodes without the need for cryogenic cooling.
使用单光子探测器进行量子测量正在为遥感、量子密码学和量子计算等多个领域开辟有趣的新视角。一类特别具有挑战性的应用依赖于对相关单光子的同时检测。在可见光和近红外波长范围内，确实存在合适的单光子探测器。然而，低探测器量子效率或过高的噪声阻碍了它们在中红外（MIR）领域的应用。因此，对于 MIR 应用来说，快速且高效的单光子探测器是非常需要的。在这里，我们通过演示室温下大约 3.1μm 的非简并双光子符合测量，为 MIR 中的量子测量铺平了道路。该实验基于通过高效上转换模块将 MIR 辐射转换到可见光区域的光谱转换。然后，使用低噪声硅雪崩光电二极管检测上转换对，而无需低温冷却。
