Carrier-Frequency Distance Dependence of a Pulse Propagating in a Two-Level System
- 1 August 1973
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review A
- Vol. 8 (2) , 1084-1110
- https://doi.org/10.1103/physreva.8.1084
Abstract
A study is made of the distance dependence of carrier phase and average frequency of an electromagnetic pulse propagating through a quantum two-level system. Phenomenological differential equations are introduced to describe the distance rate of change of first- and second-moment deviations of the pulse carrier frequency from its original input frequency. In equilibrium the equations predict characteristics of pulse propagation in steady state. For both absorber and amplifier cases, computer plots are presented of the distance dependence of pulse shape, carrier phase, Fourier amplitude, and pulse energy for selected types of homogeneous and inhomogeneous line broadening and for specific input-pulse conditions. Off-resonance formation of a single hyperbolic secant pulse of self-induced transparency may evolve from input-pulse areas less than , as well as slightly greater than , accompanied by frequency modulation and pulse breakup. The amplification of pulsed carrier radiation is accompanied by frequency pulling toward resonance. With and without phase modulation, stability conditions for stable pulse propagation are obtained. Either frequency pulling toward or frequency pushing away from resonance is dominant for an absorber, according to the dominance, respectively, of homogeneous or inhomogeneous line broadening. In the slowly-varying-pulse-envelope approximation, a steady-state solution is found for a symmetrically-phase-modulated pulse propagating in an amplifier with scattering losses. The mean carrier frequency for the pulse is displaced off resonance by one linewidth above the resonance transition frequency of a homogeneously broadened system.
Keywords
This publication has 8 references indexed in Scilit:
- Self-Induced Transparency in Atomic RubidiumPhysical Review A, 1972
- A preferred pulse in self-induced transparencyOptics Communications, 1971
- Some Results on Coherent Radiative Phenomena withPulsesPhysical Review A, 1971
- Self induced transparency in near resonant mediaPhysics Letters A, 1970
- Light pulse propagation in homogeneously broadened amplifiersPhysics Letters A, 1970
- Self-Induced TransparencyPhysical Review B, 1969
- Exact solution of a π-pulse problemIEEE Journal of Quantum Electronics, 1968
- Theory of optical maser amplifiersIEEE Journal of Quantum Electronics, 1965