Seminary of Nicolas Joly

Nicolas Joly , Max Planck Institute for the Science of Light/Friedrich-Alexander-Universität, Erlangen (Germany) Microstructured fibers for quantum optics Photonic crystal fibers (PCFs) are an ideal platform for all kinds of non-linear optics experiments and for the generation of photon pairs and twin beams, ought to the possibility to shape their non-linearity and dispersion. In this talk we will present several applications of PCFs for the generation and manipulation of quantum sources. First, we will show the generation of tunable photon pairs generated in a suspended core fiber filled with argon [1]. In hollow fiber, the filling gas serves as the gain for the process. By using a noble gas - monoatomic - one can even avoid the Raman scattering that arises from random molecular vibrations and which produces unwanted noise and usually degrades the quality of fiber-based sources. In such a system, correlated photon sources can be designed with easily tunable frequencies. The generated photons can be more than an octave apart [2,3]. Rather than trying to make our system immune to noise from Raman scattering, we will see that if molecular vibrations are carefully prepared, stimulated Raman scattering can be used for single photon frequency conversion. The phenomenon is linear and requires that phase matching be verified. We have recently demonstrated the conversion of the 125 THz single photon frequency, while preserving the correlations of the original entangled pair [4]. [1] J. Hammer, et al, Phys. Rev Res, 2, 012079 (2020) [2] M. Finger, et al, PRA 95, 053814 (2017) [3] S. Lopez-Huidobro, et al, Opt. Lett. 46, 4033 (2021) [4] R. Tyumenev, et al, Science, 376, 621 (2022)