High Spectral Purity Millimeter-Wave Generated from Millihertz-Linewidth Lasers

We demonstrate photonic-assisted tunable millimeter-wave generation via heterodyne beating of two common-cavity Brillouin lasers with sub-millihertz «0.1 mHz) fundamental linewidth, the measured phase noise of multi-frequency millimeter-wave carriers are down to −110 dBc/Hz@l kHz offset; −130 dBc/Hz@10 kHz offset, the lowest reported to date.