Joint Inversion of Rayleigh and Love Dispersion Curves Extracted from Ambient Seismic Noise Based on Secular Function

Traditional multi-mode dispersion curve inversion requires correct mode discrimination. However, when the stratum contains complex structures such as low-speed soft interlayer or high-speed hard interlayer, the dispersion curve may show phenomena such as “mode kissing” and “mode jumping”, which can easily cause mode misjudgment and lead to erroneous inversion results. Based on the “secular function”, this paper constructs a new type of objective function applied to the inversion of dispersion curve. This objective function does not require prior mode discrimination, which effectively solves the “mode misjudgment” problem of multi-mode dispersion curve inversion. The joint inversion of Rayleigh and Love dispersion curves extracted from ambient seismic noise is used to improve the constraint of the inversion and avoid the inversion falling into a local minimum in the case of a large-scale search of parameters. Finally, a numerical simulation was performed to verify the feasibility of the new inversion method.

Snapshot Angle-Resolved Spectroscopy and Its Application for Study of Highly Efficient Polariton OLEDs

The multifunctional snapshot angle-resolved spectroscopy (ARS) system capable of electroluminescence, photoluminescence, and reflectance measurements for thin film devices is developed based on the k-space imaging technique. Compared with the conventional goniometric ARS system, this snapshot spectroscopy system offers great advantages of rapid and simple measurement, suitable for characterizing thin film devices that are unstable or degraded under long-time or high-power driving conditions, such as OLEDs. We perform a detailed calibration of the snapshot system and show that the measured results closely match with those obtained using a goniometric system. Furthermore, we show the capabilities of the system with application in studying polariton OLEDs. The result provides comprehensive information on the polariton mode dispersion and emission distribution, and shows an effective radiative pumping of the lower polariton branch for high emission efficiency.

Effects of Mode Dispersion on Cross-phase modulation on Mode Division Multiplexed Optical Fibers

<div>The concept of mode division multiplexing also known as space division multiplexing was introduced as an alternative to combat the approaching capacity crunch in single mode fibers. Just like single mode fibers, space division multiplexed fibers will experience non-linearity at a different level and studies have shown that some linear effects can be beneficial in combating the nonlinear interference. This study aims to identify the benefits accrued when these linear effects are implemented by exploring the already existing models defined in the literature.</div>

Effects of Mode Dispersion on Cross-phase modulation on Mode Division Multiplexed Optical Fibers

<div>The concept of mode division multiplexing also known as space division multiplexing was introduced as an alternative to combat the approaching capacity crunch in single mode fibers. Just like single mode fibers, space division multiplexed fibers will experience non-linearity at a different level and studies have shown that some linear effects can be beneficial in combating the nonlinear interference. This study aims to identify the benefits accrued when these linear effects are implemented by exploring the already existing models defined in the literature.</div>

Analysis of optical Kerr effect on effective core area and index of refraction in single-mode dispersion shifted and dispersion flattened fibers

A new technique is presented for computing very useful propagation parameters like effective core area and effective index of refraction of mono-mode dispersion shifted and dispersion flattened fibers both in the presence and in the absence of Kerr nonlinearity. The technique involves application of accurate but simple expressions for modal fields developed by Chebyshev formalism. The study of the influence of Kerr nonlinearity on the aforementioned parameters, however, requires the application of the method of iteration. For the purpose of such investigation, in linear as well as nonlinear region, we take some typically used dispersion shifted and dispersion flattened fibers and we show that the results found by our simple formalism are in excellent agreement with those obtained by using complex finite element method. Further, the necessary evaluation by our simple method needs very less computations. Thus, our formalism generates ample opportunity for applications in many areas in the field of nonlinear optics.