A Position Sensitive X-ray Spectrophotometer using Microwave Kinetic   Inductance Detectors
  The surface impedance of a superconductor changes when energy is absorbed and Cooper pairs are broken to produce single electron (quasiparticle) excitations. This change may be sensitively measured using a thin-film resonant circuit called a microwave kinetic inductance detector (MKID). The practical application of MKIDs for photon detection requires a method of efficiently coupling the photon energy to the MKID. We present results on position sensitive X-ray detectors made by using two aluminum MKIDs on either side of a tantalum photon absorber strip. Diffusion constants, recombination times, and energy resolution are reported. MKIDs can easily be scaled into large arrays. 
Benjamin A. Mazin, Megan E. Eckart, Bruce Bumble, Sunil Golwala, and   Peter K. Day, Jonas Zmuidzinas, and Fiona A. Harrison