Generating quantum states of surface plasmon-polariton pairs with a nonlinear nanoparticle

© 2019 IEEE. In the last few years, materials with strong second-order optical nonlinearity such as gallium arsenide, barium titanate and transition metal dichalcogenides have attracted significant attention, because they for the first time allowed efficient nonlinear optical interactions on the sub-micron scales. One of such nonlinear optical interactions - spontaneous parametric down-conversion (SPDC) - allows the generation of pairs of correlated photons and can enable photon entanglement [1]. This is the foundation of many quantum optical applications ranging from secure communication to ultrafast quantum computing [2]. The key challenges in this field are efficiency and the generation of on-demand quantum states

Spontaneous Parametric Down-Conversion and Quantum Walks in Arrays of Quadratic Nonlinear Waveguides

We analyze the process of simultaneous photon pair generation and quantum walks realized by spontaneous parametric down conversion of a pump beam in a quadratic nonlinear waveguide array. We demonstrate that this flexible platform allows for creating quantum states with different spatial correlations. In particular, we predict that the output photon correlations can be switched from photon bunching to antibunching controlled entirely classically by varying the temperature of the array or the spatial profile of the pump beam.Comment: 4 pages, 4 figure

Tunable generation of entangled photons in a nonlinear directional coupler

The on-chip integration of quantum light sources has enabled the realization of complex quantum photonic circuits. However, for the practical implementation of such circuits in quantum information applications it is crucial to develop sources delivering entangled quantum photon states with on-demand tunability. Here we propose and experimentally demonstrate the concept of a widely tunable quantum light source based on spontaneous parametric down-conversion in a nonlinear directional coupler. We show that spatial photon-pair correlations and entanglement can be reconfigured on-demand by tuning the phase difference between the pump beams and the phase mismatch inside the structure. We demonstrate the generation of split states, robust N00N states, various intermediate regimes and biphoton steering. This fundamental scheme provides an important advance towards the realization of reconfigurable quantum circuitry

Quantum random number generation using a solid state single photon source

© COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only. In this work we couple bright room-Temperature single-photon emission from a hexagonal boron nitride atomic defect into a laser-written photonic chip. We perform single photon state manipulation with evanescently coupled waveguides acting as a multiple beam splitter, and generate a superposition state maintaining single photon purity. We demonstrate that such states can be utilized for quantum random number generation

Multidimensional synthetic chiral-tube lattices via nonlinear frequency conversion

Geometrical dimensionality plays a fundamentally important role in the topological effects arising in discrete lattices. While direct experiments are limited by three spatial dimensions, the research topic of synthetic dimensions implemented by the frequency degree of freedom in photonics is rapidly advancing. The manipulation of light in such artificial lattices is typically realized through electro-optic modulation, yet their operating bandwidth imposes practical constraints on the range of interactions between different frequency components. Here we propose and experimentally realize all-optical synthetic dimensions involving specially tailored simultaneous short- and long-range interactions between discrete spectral lines mediated by frequency conversion in a nonlinear waveguide. We realize triangular chiral-tube lattices in three-dimensional space and explore their four-dimensional generalization. We implement a synthetic gauge field with nonzero magnetic flux and observe the associated multidimensional dynamics of frequency combs, all within one physical spatial port. We anticipate that our method will provide a new means for the fundamental study of high-dimensional physics and act as an important step towards using topological effects in optical devices operating in the time and frequency domains.Comment: 20 pages, 6 figure

Complete conversion between one and two photons in nonlinear waveguides: Theory of dispersion engineering

High-efficiency photon-pair production is a long-sought-after goal for many optical quantum technologies, and coherent photon conversion (CPC) processes are promising candidates for achieving this. We show theoretically how to control coherent conversion between a narrow-band pump photon and broadband photon pairs in nonlinear optical waveguides by tailoring frequency dispersion for broadband quantum frequency mixing. We reveal that complete deterministic conversion as well as pump-photon revival can be achieved at a finite propagation distance. We also find that high conversion efficiencies can be realised robustly over long propagation distances. These results demonstrate that dispersion engineering is a promising way to tune and optimise the CPC process. © 2022 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft.Australian Research Council, ARC: DE180100070, DP160100619, DP190100277, FT170100399; Ministry of Education and Science of the Russian Federation, Minobrnauka: AAAA-A18-118020190095-4The authors acknowledge the support by the Australian Research Council (DE180100070, DP160100619, DP190100277). NKL is funded by the Australian Research Council Future Fellowship (FT170100399). Batalov S V acknowledges support by the Ministry of Education and Science of the Russian Federation (the theme ‘Quantum’, No. AAAA-A18-118020190095-4)