A review of the lumped element kinetic inductance detector

The Lumped Element Kinetic Inductance Detector (LEKID) was first proposed in 2007 as a solution for using kinetic inductance type detectors for sub-mm astronomy (450 - 200 mu m). Since then the LEKID has been demonstrated to have applications over a much wider range of wavelength. Examples of this have been 200 mu m detection of a cold blackbody and successful testing of a demonstration array operating at 2mm on the IRAM telescope in October 2009. Due to the combination of absorber and detector in a single element, the LEKID is an extremely simple detector to fabricate requiring only one deposition and etch step to produce an array of up to 1000 pixels multiplexed onto a single feedline. The LEKID is also a very compact detector making it ideal for producing arrays with high filling factors. The suitability of the LEKID for use in large arrays has prompted a return visit to the IRAM telescope with a dual band instrument in 2010. This presentation will review the progress to date of the LEKIDs development and outline design considerations for producing LEKIDs for future FIR astronomical instruments such as SPICA. Also reviewed will be possible applications for the LEKID outside sub-mm and mm astronomy.