Finite-Difference Time-Domain Analysis of Laser Action in Cholesteric Photonic Liquid Crystal

Abstract

We have numerically investigated lasing dynamics in cholesteric liquid crystal (CLC) with gain by an auxiliary differential equation finite-difference time-domain (ADE-FDTD) method in which the FDTD method is coupled with a rate equation in a four-level energy structure. Circularly polarized lasing was achieved at the photonic band edge above threshold pumping. Our model opens a way for a computational design of the CLC laser on the basis of numerical simulation to realize a more efficient device architecture for a greatly reduced lasing threshold, which is still under extensive study.

Light emission from dye-doped cholesteric liquid crystals at oblique angles: Simulation and experiment

“…This analytical approach is limited to basic structures and directions for which the eigenmodes are known. For more complex structures and/or emission directions for which the eigenmodes are not known, "brute force" numerical methods such as FDTD (finite-difference time domain) [18] can be used. However, such methods consume a lot of computer time and memory.…”

Exploring Time‐Resolved Multiphysics of Active Plasmonic Systems with Experiment‐Based Gain Models

“…Among them, due to the accurate treatment of quantum properties of the gain medium, the time‐domain multiphysics approach is viewed as the most powerful method, in which a finite‐difference, finite‐volume, or a finite element time‐domain method is coupled to a multi‐level system through auxiliary differential equations . Using a classical FDTD scheme, this approach has been applied to investigate lasing dynamics, and interpret lasing experiments . Recently, the Maxwell‐Bloch‐Langevin (MBL) approach has been introduced and broadly used by the Hess group to account for the spatial and temporal fluctuations providing a more accurate means of simulating amplified spontaneous emission.…”

Effects of Photonic Band Gap of Cholesteric Liquid Crystal on Chemiluminescence

“…We have recently reported the enhancement of emission intensity of luminol reaction when the reaction occurs between two glass cells filled with CLC materials (CLC reflectors) [6]. For a wide variety of applications of CLC materials to chemiluminescence sensors, the fine-tunable photonic band gap (PBG) of CLC by changing the composition ratio of nematic liquid crystalline (NLC) materials and chiral dopants should be investigated in more detail [7] Here, we report the PBG-dependence of the enhancement of emission intensity of luminol reaction using the CLC reflectors with different PBG wavelengths.…”