By exploiting recent developments associated with parity–time (PT) symmetry in optics, we here propose a new avenue in realizing single-mode large area laser amplifiers. This can be accomplished by utilizing the abrupt symmetry breaking transition that allows the fundamental mode to experience gain while keeping all the higher order modes neutral. Such PT-symmetric structures can be realized by judiciously coupling two multimode waveguides, one exhibiting gain while the other exhibits an equal amount of loss. Pertinent examples are provided for both semiconductor and fiber laser amplifiers.
© 2012 Optical Society of America
Lasers and Laser Optics
Original Manuscript: October 26, 2011
Revised Manuscript: January 9, 2012
Manuscript Accepted: January 15, 2012
Published: February 17, 2012
Mohammad-Ali Miri, Patrik LiKamWa, and Demetrios N. Christodoulides, "Large area single-mode parity–time-symmetric laser amplifiers," Opt. Lett. 37, 764-766 (2012)