A note on the use of dust plasma crystals as tunable THz filters

We discuss theoretically the possible use of plasma crystals as tunable filters in the terahertz (THz) regime. Estimates of transmittance are based on previous analyses of crystalline colloid array filters that Bragg diffract incident light. We consider how the plasma crystal might be tuned magnetically if it is composed of paramagnetic dust grains. Varying an external magnetic field would change the spacing between the dust grains due to induced dipole forces, thus changing the diffracted wavelength. Some possible experimental parameters are discussed.