Femtosecond nonlinear optical properties of polycyclic aromatic hydrocarbon-based Benzo[e]pyrene derivatives

Tunable near-infrared emission and three-photon absorption in lanthanide-doped double perovskite nanocrystals

“…As the intense laser beam is present in the nonlinear medium, the nonlinear refractive (NLR) index ( n 2 ) comes into picture and it alters the refractive index of the medium. 71 The following relationship 72 exists between the nonlinear phase shift and the nonlinear refractive index:Δ Φ = kI 0 n 2 L eff ,where k = 2π/ λ is the wave vector, I 0 is the peak intensity of the incident laser beam at the focus, and L eff represents the effective path length inside the sample. Fig.…”

“…As the intense laser beam is present in the nonlinear medium, the nonlinear refractive (NLR) index (n 2 ) comes into picture and it alters the refractive index of the medium. 71 The following relationship 72 exists between the nonlinear phase shift and the nonlinear refractive index:…”

Novel metallated imidazole phthalocyanines: synthesis, ultrafast excited-state carrier dynamics and multiphoton absorption properties

“…One can expect nonlinear absorption processes such as two-photon absorption (2PA) or three-photon absorption (3PA). A three-level energy model 46 for these Pc systems interacting with the ultrashort laser has been taken into account in our calculations to fully explain the nonlinear behaviour using theoretical modeling. According to analysis of the target modeling of fs-TAS results, the transition to the first triplet excited state from the first singlet excited state occurs more slowly (Bns) than the excitation laser pulse duration (70 fs).…”

Harnessing Coherent Light–Matter Interactions for All-Optical Switching and Logic Gate Applications with Macrocyclic Phthalocyanines

“…NLO deals with the study of the variation of the polarization density with the incident electric field of light. Since the last few decades, the NLO field has been developed in photonics and optoelectronics, including electro-optic sensors, and telecommunications. − Along with inorganic materials, − organic materials also show good NLO properties due to their highly delocalized π-conjugated electrons. ,− The organic molecules possess large and fast nonlinear responses with easy processing, providing advantages for optical applications . Due to the nonlinear Kerr effect, the NLO parameter nonlinear refractive index (NLR) n 2 of material changes with varying the value of the input intensity of the incident light. , There are various processes for measuring the third-order polarizabilities, such as four-wave mixing (FWM), the optical Kerman method, and the Z-scan method. − Nonlinear coherent light–matter interaction spatial self-phase modulation , is an easy-to-handle but robust standard experiment to precisely evaluate various NLO parameters such as nonlinear refractive index ( n 2 ) and third-order nonlinear optical susceptibility [χ (3) ].…”