  We investigate the effect of parity-time (PT)-symmetric optical potentials on
the radiation of achiral and chiral emitters. Mode coalescence and the
appearance of exceptional points lead to orders-of-magnitude enhancements in
the emitted dipole power. Further, the emitter can be tuned to behave as a
strong optical source or absorber based on the non-Hermiticity parameter.
Chiral enantiomers radiating near PT metamaterials exhibit a 4.5-fold
difference in their decay rate. The results of this work could enable new
atom-cavity interactions for quantum optics, as well as all- optical
enantio-specific separation.
