Photonic crystals are periodic dielectric structures that exhibit photonic band gaps that strongly depend on the geometry of the lattice elements and material properties [1,2]. Since the design parameters of the photonic crystal structure are amenable to modification and adjustments, light can be manipulated and easily controlled, guided, and trapped in these structures [3]. Conventional photonic crystals have high-symmetry unit cells. Low-rotational-symmetry structures are formed by breaking the high symmetry in the photonic crystal unit cell. Low-symmetry structures are more sensitive to light manipulation and provide more control and flexibility over light with geometric and structural diversity [4]. In this study, the resonance effect in the cavity structure of a square-lattice photonic crystal composed of C2-type low-symmetry dielectric rods is investigated. The band structure, equi-frequency contours, and transmission spectra of the low-rotational-symmetry photonic crystal are obtained with Lumerical and MEEP software to examine the resonance [5,6]. Analyzing optical properties through symmetry manipulation and resonance refraction will contribute to understanding light collimation and confinement.

References:

[1] Yablonovitch E., 1993, “Photonic band-gap structures”, J. Opt. Soc. Am. B 10 283–95

[2] John S., 1987, “Strong localization of photons in certain disordered dielectric superlattices”, Phys. Rev. Lett. 58 2486–9

[3] Joannopoulos J D. et al, 2008, “Photonic Crystals: Molding the Flow of Light Second Edition (Princeton University Press)

[4] Zekeriya M Yuksel et al 2024, “Enhanced self-collimation effect by low rotational symmetry in hexagonal lattice photonic crystals”, Phys. Scr. , 99, 065017.

[5] Lumerical FDTD Solutions, Inc. http://www.lumerical.com.

[6] Oskooi, A. F. et al, 2010, “Meep: A flexible free-software package for electromagnetic simulations by the FDTD method”, Comput. Phys. Commun., vol. 181, no. 3, pp. 687–702, 2010.