The QITE team just published in Phys. Rev. Lett. its work on the generation of spatial entanglement in nonlinear waveguide arrays, in collaboration with C2N and INPHYNI.
Combining the generation and manipulation of complex quantum states of light on a single chip is a crucial step toward practical quantum information technologies. This work addresses this challenge by merging two fundamental concepts—nonlinear optics and quantum walks—to realize a compact and versatile source of photon pairs exhibiting strong spatial correlations, that cannot be produced by classical means.
Traditional photonic devices generate and manipulate photons in a step-by-step fashion, using a sequence of discrete optical components. By contrast, nonlinear waveguide systems offer a promising alternative where photons can be generated and interfere in a continuous manner, unveiling novel capabilities within a reduced footprint. In this work, photon pairs produced by parametric generation in an AlGaAs waveguide array hop randomly from one waveguide to the other during their propagation—they experience quantum walks, a non-classical analogue of the famous Galton board. By tailoring the pump beam, the output state can be reconfigured, enabling the creation of a wide variety of spatially entangled states of light. Combined with the ability to engineer at will the device geometry, this novel approach opens exciting prospects for simulating with photons physical problems that are otherwise difficult to access in condensed matter.
Reference :
Tunable generation of spatial entanglement in nonlinear waveguide arrays
A. Raymond, A. Zecchetto, J. Palomo, M. Morassi, A. Lemaître, F. Raineri, M. Amanti, S. Ducci, F. Baboux
Phys. Rev. Lett. 133, 233602 (2024)
À lire aussi
An optomechanical disk in its fundamental state of motion
The motion of a mesoscopic mechanical resonator can exhibit quantum behavior when cooled to very low temperatures. In particular, it can reach its ground state and cease to vibrate. Using light as a probe, the LIME team at the MPQ laboratory demonstrated that...
Exact low-energy duality in superconducting quantum circuits
The THEORIE team, in collaboration with Michel H. Devoret, has published a theoretical study in Physical Review Letters demonstrating an exact low-energy duality in circuits where a Josephson junction is coupled to a multi-mode environment. These systems exhibit a...
Multiphysics optomechanical sensing of a liquid on the micron scale
The LIME team at MPQ laboratory, in collaboration with CEA LETI in Grenoble, has published an article in Microsystems & Nanoengineering presenting an optomechanical platform for characterizing the rheological, optical, and thermal properties of fluids at the...
Biphoton state generation and engineering with bright hybrid III–V/silicon photonic devices
The QITE team at the MPQ Laboratory, in collaboration with STMicroelectronics, C2N, and INPHYNI, published a paper in Optica Quantum on the generation and engineering of two-photon states using III-V/SOI hybrid devices. Artist’s sketch of...