Lasers without inversion: Interference of lifetime-broadened resonances
Abstract
We show that if two upper levels of a four-level laser system are purely lifetime broadened, and decay to an identical continuum, then there will be an interference in the absorption profile of lower-level atoms, and that this interference is absent from the stimulated emission profile of the upper-level atoms. Laser amplification may then be obtained without inversion. Examples include interfering autoionizing levels, and tunneling systems.
- Publication:
-
Physical Review Letters
- Pub Date:
- February 1989
- DOI:
- 10.1103/PhysRevLett.62.1033
- Bibcode:
- 1989PhRvL..62.1033H
- Keywords:
-
- Electromagnetic Interference;
- Laser Outputs;
- Optical Resonance;
- Photoabsorption;
- Autoionization;
- Population Inversion;
- Power Gain;
- Radiative Lifetime;
- Lasers and Masers;
- 42.55.Bi;
- 32.70.Jz;
- 32.80.Dz;
- Line shapes widths and shifts;
- Autoionization