Nonlinear interactions of finite amplitude and weak subharmonic plane waves-Phase-dependent parametric amplification

• Published in: Journal of the Acoustical Society of Japan (E) Vol. 6; no. 3; pp. 155 - 160
• Main Authors: Kamakura, Tomoo, Ikegaya, Kazuo, Chou, Ing-Min
• Format: Journal Article
• Language: English
• Published: Acoustical Society of Japan 1985
• ISSN: 0388-2861; 2185-3509
• DOI: 10.1250/ast.6.155

Fenlon's solution of tone-tone interaction is used to derive parametric amplification of a weak subharmonic wave being interacted with an intense pump wave. The theory only the quadratic nonlinearity of medium is taken into consideration accounts for clear effects of the initial phase of the weak signal on the parametric amplification. In particular, the degenerate case where the weak signal frequency is half of the pump, the amplification varies dramatically with the initial phase. However, the amplification of higher order subharmonic wave becomes independent of the initial phase. Experiments for half and one-third subharmonics are performed in a plane acoustic wave tube. The experimental trends of the phase-dependent parametric amplification are predicted well by the theory.