Highly tunable photonic crystal filter for the terahertz range

By use of an incipient ferroelectric, SrTiO3, as a defect material inserted into a periodic structure of alternating layers of quartz and high-permittivity ceramic, thermal tuning of a single defect mode over the entire lowest forbidden band was obtained. The tunability of this compact structure reached 60%. (C) 2005 Optical Society of America.