Nonlinear multimode photonics: nonlinear optics with many degrees of freedom

Abstract

The overall goal of photonics research is to understand and control light in new and richer ways to facilitate new and richer applications. Many major developments to this end have relied on nonlinear optical techniques, such as lasing, mode-locking, and parametric downconversion, to enable applications based on the interactions of coherent light with matter. These processes often involve nonlinear interactions between photonic and material degrees of freedom spanning multiple spatiotemporal scales. While great progress has been made with relatively simple optimizations, such as maximizing single-mode coherence or peak intensity alone, the ultimate achievement of coherent light engineering is complete, multidimensional control of light–light and light–matter interactions through tailored construction of complex optical fields and systems that exploit all of light’s degrees of freedom. This capability is now within sight, due to advances in telecommunications, computing, algorithms, and modeling. Control of highly multimode optical fields and processes also facilitates quantitative and qualitative advances in optical imaging, sensing, communication, and information processing since these applications directly depend on our ability to detect, encode, and manipulate information in as many optical degrees of freedom as possible. Today, these applications are increasingly being enhanced or enabled by both multimode engineering and nonlinearity. Here, we provide a brief overview of multimode nonlinear photonics, focusing primarily on spatiotemporal nonlinear wave propagation and, in particular, on promising future directions and routes to applications. We conclude with an overview of emerging processes and methodologies that will enable complex, coherent nonlinear photonic devices with many degrees of freedom.

Experimental observation of spontaneous emission of space-time wavepacket in a multimode optical fiber

“…The resulting 2D+1 ST wavepacket propagates with a deterministic group-velocity and it results from a linear superposition of fiber modes with an engineered spatiotemporal spectrum. Even if the configuration of spontaneous emergence implies that the conical wave is not fully non-dispersive and non-diffractive, this simple and alternative approach opens the way to future extensive studies of multidimensional ST wavepackets with fiber and waveguide technologies [13,[25][26][27]. Finally, our results also prove the general capabilities of MM-UPPE modeling for nonlinear multimode propagation problems.…”

Experimental Observation of the Spontaneous Emission of a Space–Time Wavepacket in a Multimode Optical Fiber

“…The resulting 2D+1 ST wavepacket propagates with a deterministic group-velocity and it results from a linear superposition of fiber modes with an engineered spatiotemporal spectrum. Even if the configuration of spontaneous emergence implies that the conical wave is not fully nondispersive and nondiffractive, this simple and alternative approach opens the way to future extensive studies of multidimensional ST wavepackets with fiber and waveguide technologies. ,− Finally, our results also prove the general capabilities of MM-UPPE modeling for nonlinear multimode propagation problems.…”

Design and manufacturing of efficient computer-generated volume holograms in glass

“…We believe that our results represent an important step towards the realization of robust and highly integrated 3D holographic light shapers for many important application fields, such as information transport [8], optical computing [9,10,11,12,13], the imaging through multimode fibers [19] and nonlinear photonics [20]. They may further help to obtain fundamental insights in the behaviour of quantum states of light upon scattering [21].…”