One principal advantage is that the laser-cooled atoms are unaffected by Johnson noise which sets the ultimate limit in semiconductor (or vacuum tube) based sys

One principal advantage is that the laser-cooled atoms are unaffected by Johnson noise which sets the ultimate limit in semiconductor (or vacuum tube) based systems. However, their stated sensitivity of -120 dBm/Hz is more than 50 dB above the Johnson noise at room temperature. They have a lot of work to do until this becomes relevant.