Study on the Gain Material with Four Energy Level Model Using FDTD Method

Hui Xue, Zhixiang Huang, Xianliang Wu

1Key Laboratory of Intelligent Computing and Signal Processing, Anhui University, Hefei, China 2Department of Physics and Electronic Engineering Hefei Normal University, Hefei, China.
Key Laboratory of Intelligent Computing and Signal Processing, Anhui University, Hefei, China.

DOI: 10.4236/opj.2013.32B004                

Abstract

A faster numerical method based on FDTD for the four energy level atomic system is present here. The initial conditions for the electrons of each level are achieving while the fields are in steady state. Polarization equation, rate equations of electronic population and Maxwell’s equations were used to describe the coupling between the atoms and electromagnetic wave. Numerical simulations, based on a finite-difference time-domain (FDTD) method, were utilized to obtain the population inversion and lasing threshold. The validity of the model and its theory is confirmed. The time, which we can observe the lasing phenomenon, is much shorter in our new model. Our model can be put into using in large scale simulations in mutiphysics to reduce the total simulated time.

Keywords

Finite-Difference Time-Domain; Gain Material; Lasing

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Anan Fang, Thomas Koschny and Costas M Soukoulis, “Lasing in metamaterial nanostructures,” Journal of Optics, Vol. 12, No. 2, 2010, p. 024013. doi:10.1088/2040-8978/12/2/024013
[2]	J. Singh, “Semiconductor Optoelectronics: Physics and Technology,” McGraw-Hill, 1995.
[3]	M.O. Scully and M.S. Zubairy, “Quantum Optics”, Cambridge University Press, Cambridge, England, 1997. doi:10.1017/CBO9780511813993
[4]	A. Taflove, “Computational Electrodynamics: The Finite-Difference Time-Domain Method,” Artech House, 1995.
[5]	P. Goorjian and A. Taflove, “Direct Time Integration of Maxwells Equations in Nonlinear Dispersive Media for Propagation and Scattering of Femtosecond Electromagnetic Solitons,” Optics letters, Vol. 17 No. 3, 1992, pp. 180-182. doi:10.1364/OL.17.000180
[6]	P. Goorjian, A. Taflove, R. Joseph and S. Hagness, “Computational Modeling of Femtosecond Optical Solitons from Maxwell’s Equations,” Quantum Electronics, Vol. 28, No. 10, 1992, pp. 2416-2422. doi:10.1109/3.159548
[7]	R. Ziolkowski, J. Arnold and D. Gogny, “Ultrafast Pulse Interactions with Two-Level Atoms,” Physical Review A, Vol. 52, No. 4, 1995, pp. 3082-3094. doi:10.1103/PhysRevA. 52.3082