At different scales, from molecular systems to technological infrastructures, physical systems group in structures which are neither simply regular or random, but can be represented by networks with complex shape. Proteins in metabolic structures and the World Wide Web, for example, share the same kind of statistical distribution of connections of their constituents. In addition, the individual elements of natural samples, like atoms or electrons, are quantum objects. Hence replicating complex networks in a scalable quantum platform is a formidable opportunity to learn more about the intrinsic quantumness of real world and for the efficient exploitation of quantum-complex structures in future technologies. Future trusted large-scale communications and efficient big data handling, in fact, will depend on at least one of the two aspects -quantum or complex- of scalable systems, or on an appropriate combination of the two
Spectrally shaped and pulse-by-pulse multiplexed multimode squeezed states of light
Tiphaine Kouadou, Francesca Sansavini, Matthieu Ansquer, Johan Henaff, Nicolas Treps, Valentina Parigi APL Photonics 8, 086113 (2023)
We demonstrate the simultaneous generation of 21 squeezed spectral modes at 156 MHz. We exploit the full repetition rate and the ultrafast shaping of a femtosecond light source to combine, for the first time, frequency- and time- multiplexing in multimode squeezing.
Other references:
-L. La Volpe, S. De, T. Kouadou, D. Horoshko, M. I. Kolobov, C. Fabre, V. Parigi, and N. Treps, Multimode single-pass spatio-temporal squeezing, Optics Express, Vol.28 pp 12385-12394 (2020)
Multimode Squeezed State for Reconfigurable Quantum Networks at Telecommunication Wavelengths
Victor Roman-Rodriguez, David Fainsin, Guilherme L. Zanin, Nicolas Treps, Eleni Diamanti, Valentina Parigi arXiv:2306.07267 (2023)
Experimental source of multimode squeezed states of light at telecommunication wavelengths. Generation at such wavelengths is especially important as it can enable quantum information processing, communication, and sensing beyond the laboratory scale. We measured significant squeezing in more than 21 frequency modes, with a maximum squeezing value exceeding 2.5 dB. We demonstrate multiparty entanglement by measuring the state's covariance matrix. Finally, we show the source reconfigurability by preparing few-node cluster states and measure their nullifier squeezing level.
Other references:
-V. Roman-Rodriguez, B. Brecht, S. Kaali, C. Silberhorn, N. Treps, E. Diamanti, V. Parigi, Continuous variable multimode quantum states via symmetric group velocity matching, New J. Phys. 23 043012 (2021)
Routing in CV quantum networks
Federico Centrone, Frederic Grosshans, and Valentina Parigi Cost and routing of continuous-variable quantum networks, Phys. Rev. A 108, 042615 (2023) , or arXiv 2108.08176
F. Sansavini and V. Parigi, Continuous Variables Graph States Shaped as Complex Networks: Optimization and Manipulation, Entropy 22, 26 (2020)
Non-Gaussian CV quantum states
M. Walschaers, N. Treps, B. Sundar, L. D. Carr, V. Parigi Emergent complex quantum networks in continuous-variables non-Gaussian states, Quantum Sci. Technol. 8 035009 (2023) or arXiv 2012.15608
G. Roeland, S. Kaali, V. Roman Rodriguez, N. Treps, V. Parigi, Mode-selective single-photon addition to a multimode quantum field, New Journal of Physics 24 (4), 043031 (2022)
V. Cimini, M. Barbieri, N. Treps, M. Walschaers, and V. Parigi, Neural Networks for Detecting Multimode Wigner Negativity, Phys. Rev. Lett. 125, 160504 (2020) or arXiv 2003.03343
Experimental simulation of complex quantum environment
P. Renault, J. Nokkala, G. Roeland , N. Y. Joly R. Zambrini, S. Maniscalco, J. Piilo N. Treps, V. Parigi, Experimental optical simulator of reconfigurable and complex quantum environment, PRX Quantum 4, 040310 (2023)
Quantum optical reservoir computing
J Henaff, M Ansquer, MC Soriano, R Zambrini, N Treps, V Parigi Optical phase encoding in pulsed approach to reservoir computing arXiv:2401.14073 (2023)
J. Nokkala, R. Martínez-Peña, G. L. Giorgi, V. Parigi, M. C Soriano, R. Zambrini, Gaussian states of continuous-variable quantum systems provide universal and versatile reservoir computing, Communications Physics volume 4, Article number: 53 (2021)