Ultra narrowband detection scheme for dark photon / axion around 30 GHz

We demonstrated that ultra narrowband filtering at 30 GHz dramatically enhances the signal-to-noise ratio to search for dark matter candidates which couple to millimeter waves. A coherent signal relatively locked between a synthesizer and a signal analyzer can be clearly distinguished from incoherent blackbody radiation after real time FFT over a long period. We propose a novel experiment for studying dark matter candidates.