Topological edge state phenomena in acoustics and ultrasonics have been widely studied and are treated as an active area of research in the field of physics. Design methodologies capable of synthesizing materials and structures having better control on the energy propagation to attain topological effects can be applied to countless real-world applications. And phononic crystals, capable of such fascinating phenomena, can be utilized better. Another major topic that may help to strengthen pre-modeled wave-guiding can be Dirac cone and Dirac-like cones. Here, we investigate different topological features and states of acoustic energy inside Phononic Crystals (PnC), utilizing Dirac-like phenomena. Moreover, the formation of dual Dirac-like cones at the center of the Brillouin zone, at different frequencies, has been reported here. Generation of multiple Dirac-like cones at the center and the edge of a Brillouin zone, which is rare and, usually, non-manipulative is demonstrated in this article. By deploying variable angular position of the square PVC resonator as a unit cell in a PnC system, the locations of the degenerated double Dirac cones have been manipulated at various frequency points. A gradual change in dispersion behavior, as well as striking topological acoustic phenomena, have been demonstrated. The proposed exploitation of the metamaterial will have important applications in acoustic computing, ultrasonic imaging, and waveguiding.
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