Parity-time symmetry in negative index optical metamaterials with parametric amplifier settings

Parity-time (PT) symmetry in an optical parametric amplifier, based on negative index metamaterial (NIM), is studied. Parametric amplification processes are considered in all the three regimes of PT symmetry, namely, below, at and above the PT threshold. It may be possible to exploit PT symmetry for various applications including compensation of loss in NIMs.