Temperature Tuning Mie Resonance-Based All-Dielectric Metamaterial

In this paper, a tunable all-dielectric left-handed metamaterial was studied by employing two types of high permittivity ceramics. The two kinds of ceramics were 0.8Ba_0.45Sr_0.55TiO₃ + 0.2MgO (BST–MgO) and 0.65Ba_0.6Sr_0.4TiO₃ + 0.35La (Mg_0.5Ti_0.5)O₃ (BST–LMT), which were cut to cubes and rods to compose the metamaterial. In the X-band, the BST–LMT rods could provide a stable, wide negative permittivity band. On the other hand, the BST–MgO cubes produced tunable negative effective permeability based on Mie resonance theory. With this cubes/rods configuration, the transmission properties are tunable via different temperatures. Simulations and experiments show that the double-negative frequency range could move from 8.4 GHz to 10.2 GHz by changing temperature from 20°C to 80°C. The fabricated all-dielectric metamaterial can provide tunable operating frequencies in a large frequency range.