Degenerate four-wave mixing and phase conjugation in a collisional plasma

Technical Report · Sun Jun 01 04:00:00 EDT 1986

DOI:https://doi.org/10.2172/5550952· OSTI ID:5550952

Federici, J F; Mansfield, D K

Although degenerate four-wave mixing (DFWM) has many practical applications in the visible regime, no successful attempt has been made to study or demonstrate DFWM for wavelengths longer than 10..mu..m. Recently, Steel and Lam established plasma as a viable DFWM and phase conjugation (PC) medium for infrared, far-infrared, and microwaves. However, their analysis is incomplete since collisional effects were not included. Using a fluid description, our results demonstrate that when collisional absorption is small and the collisional mean-free path is shorter than the nonlinear density grating scale length, collisional heating generates a thermal force which substantially enhances the phase conjugate reflectivity. When the collisional attenuation length becomes comparable to the length of the plasma, the dominant effect is collisional absorption of the pump waves. Numerical estimates of the phase conjugate reflectivity indicate that for modest power levels, gains greater than or equal to1 are possible in the submillimeter to centimeter wavelength range. This suggests that a plasma is a viable PC medium at those long wavelengths. In addition, doubly DFWM is discussed.

• Research Organization: Princeton Univ., NJ (USA). Plasma Physics Lab.
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 5550952
• Report Number(s): PPPL-2336; ON: DE86013640
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700108* -- Fusion Energy-- Plasma Research-- Wave Phenomena
ABSORPTION
COLLISIONAL PLASMA
ELECTROMAGNETIC RADIATION
FAR INFRARED RADIATION
INFRARED RADIATION
MICROWAVE RADIATION
NONLINEAR PROBLEMS
PLASMA
RADIATIONS