Strongly Coupled Systems for Nonlinear Optics

Abstract

Strong coupling is a distinct light-matter interaction regime, in which the interaction is manifested in coherent oscillations of energy between matter and a photonic subsystem. The consequence of such a strong coupling is the adjustment of the energy states of molecules and materials, which can bring about fascinating chemical and physical properties, and therefore result in advanced applications in many fields such as Bose-Einstein condensation and coherent emission, polariton lasing, superfluidity, quantum information processing, Raman scattering, chemical landscape, etc. Recently, strong coupling has also demonstrated profound impacts on the nonlinear optical (NLO) properties of molecular materials. In this review, the recent research progress in the field of strongly coupled systems for NLO applications is summarized. The underlying concepts and the detailed features of strongly coupled molecular systems are introduced, and the NLO characteristics of strongly coupled systems are reviewed. Finally, an outlook of future directions for this emerging field is given.

Phonon‐Suppressing Intermolecular Adhesives: Catechol‐Based Broadband Organic THz Generators

“…[ 65,77 ] Note also that compared to the recently proposed halide perovskite crystals for nonlinear optics, DHP‐TFS crystals exhibit much higher second‐order optical nonlinearity. [ 75,76 ]…”

“…This large second-order optical nonlinearity of DHP-TFS crystals compares favorably to other-types of nonlinear optical and THz generation materials. [16,65,[75][76][77] For example, the electrooptic coefficient of widely used inorganic THz crystals (e.g., ZnTe, GaAs, and GaP) is one order of magnitude smaller than that of the organic benchmarks. [65,77] Note also that compared to the recently proposed halide perovskite crystals for nonlinear optics, DHP-TFS crystals exhibit much higher second-order optical nonlinearity.…”

“…[65,77] Note also that compared to the recently proposed halide perovskite crystals for nonlinear optics, DHP-TFS crystals exhibit much higher second-order optical nonlinearity. [75,76] Organic crystals with a yellow color often exhibit good phase matching characteristics for THz wave generation when using both near-infrared and infrared optical pump wavelengths. [41,55] The chromophores used in yellow-color organic THz generators exhibit the wavelength of maximum absorption 𝜆 max in the range of 390-420 nm in methanol.…”

Tamm Plasmon‐Polariton Ultraviolet Lasers

“…[20] Due to the strong field confinement of TPPs, it would also be a suitable structure for investigating the effect of Rabi splitting as well as the performance of strong coupling. [21][22][23][24][25][26] Under strong coupling conditions, TPP and excitons will form a new quasi-particle-Tamm plasmon excitonpolariton. Compared with excitons, its equivalent mass is smaller, so it is easier to form Bose-Einstein condensation than excitons.…”

The universal model of strong coupling at the nonlinear parametric resonance in open cavity-QED systems

“…Nonlinear optical interactions acquire qualitatively new features in the strong-coupling regime of cavity quantum electrodynamics (QED), especially when utilizing an extreme field localization achievable in nanophotonic cavities. Even in the standard cavity QED scenario of the strong coupling at the two-wave resonance between only two degrees of freedom, e.g., between an electronic or vibrational transition in a molecule and an electromagnetic (EM) cavity mode, strong coupling has been shown to modify the properties of Raman scattering, generation of harmonics, four-wave mixing, and nonlinear parametric interactions, with applications in photochemistry, quantum information, and quantum sensing; see, e.g., [1][2][3][4][5][6][7][8][9][10][11][12].…”