Searching for low-mass axions using resonant upconversion

We present new results of a room temperature resonant AC haloscope, which searches for axions via photon upconversion. Traditional haloscopes require strong applied DC magnetic background field surrounding the haloscope cavity resonator, frequency is limited by available bore dimensions. UPLOAD, UPconversion Low-Noise Oscillator Axion Detection experiment, replaces this magnet with second microwave resonance within detector cavity, upconverts energy from axion into readout mode, accessing around beat modes. Furthermore, unlike case, experiment sensitive to newly proposed quantum electromagnetodynamical coupling term $g_{aBB}$. Two experimental approaches are outlined - one using metrology, and other power detection thermal mode. The presented, allows exclusion masses between 1.12 $-$ 1.20 $\mu eV$ above strength both $g_{a\gamma\gamma}$ $g_{aBB}$ at $3 \times 10^{-6}$ 1/GeV, after measurement period 30 days, three order magnitude improvement over our previous result.