Broadband terahertz modulation using reconfigurable mesh filters

A broadband terahertz intensity modulator based on MEMS-reconfigurable mesh filters is presented and experimentally demonstrated. Modulator operation is based on reconfiguring the geometry of a multi-layer mesh filter from a capacitive configuration to an inductive configuration, which alters device scattering parameters from a low-pass filter to a high-pass filter, respectively. The geometry of the multi-layer mesh filter is chosen to allow cut-off frequencies beyond 3 THz, enabling terahertz modulation over a broad range of frequencies. Additionally, arrays of multi-contact electrostatic MEMS switches are integrated with the multi-layer mesh filter, enabling the required geometry reconfiguration within a fully integrated and high-speed device solution. We experimentally demonstrate more than 65% modulation depth over 1.5 THz frequency band, under a modulation voltage of 30 V and modulation speeds exceeding 20 KHz.