Improvement of Ti-based Superconducting Transition Edge Sensors with Dielectric Mirror

We have improved the detection efficiency of Ti-based superconducting transition edge sensor(TES) with the integration of dielectric mirror at the operation wavelength of 1550 nm. The TES fabricated on the dielectric mirror is coupled to the optical fiber using back-side through-chip imaging. The measured effective response time is several μs and the detection efficiency is improved to 30%.