Temperature effects on the defect states in two-dimensional phononic crystals

Temperature effects on the defect states are investigated in two models, constructed by changing the temperature of the central rod and rotating it 45 degrees as well as changing the temperature of the central rod respectively. The results show that the defect modes will fall in the band gap when the surrounding temperature of phononic crystal is higher than the Curie temperature (Tc) and the temperature of central defect rod is lower than Tc in Model 1, while the defect modes will emerge in Model 2 as long as the surrounding temperature of phononic crystal is higher than Tc.