Atomic parity violation in two-photon J=0-to-1 transitions
  We present a method for measuring nuclear-spin-dependent atomic parity violation without nuclear-spin-independent background. Such measurements can be achieved by observing interference of parity-conserving and parity-violating two-photon J=0-to-1 transitions driven by collinear photons of the same frequency in the presence of an external static magnetic field. 
D. R. Dounas-Frazer and K. Tsigutkin and D. English and D. Budker
physics.atom-ph