A prototype gravitational wave detector for 100 MHz

A prototype gravitational wave detector has been constructed for observations at 100 MHz. The device uses an interaction between an electromagnetic wave and the curved spacetime of the gravitational wave. A resonance effect is used to improve the sensitivity by a factor of similar to 2000 over a narrow bandwidth. Two prototype detectors have been constructed and their outputs used in a correlation experiment to improve the sensitivity by one or more orders of magnitude, giving a noise spectral density of similar to 10(-14) Hz(-1/2) at 100 MHz. Target sources for an improved detector would include the stochastic gravitational wave background from energetic events in the very early universe and black hole interactions in higher dimensional gravitational theories. Possible technological pathways for improving the sensitivity are suggested.