Modulational instability of ion-acoustic wave packets in quantum pair-ion plasmas

TL;DR

This paper investigates how quantum effects influence the stability of ion-acoustic wave packets in pair-ion plasmas, revealing new regimes of modulational stability and instability relevant to astrophysical and laboratory plasmas.

Contribution

It introduces the quantum coupling parameter as a key factor in modulational stability and derives new stability regimes based on plasma parameters.

Findings

Quantum coupling parameter $H$ determines wave stability.

New regimes for modulational stability and instability are identified.

Growth rate of instability depends on ion density ratio and quantum effects.

Abstract

Amplitude modulation of quantum ion-acoustic waves (QIAWs) in a quantum electron-pair-ion plasma is studied. It is shown that the quantum coupling parameter $H$ (being the ratio of the plasmonic energy density to the Fermi energy) is ultimate responsible for the modulational stability of QIAW packets, without which the wave becomes modulational unstable. New regimes for the modulational stability (MS) and instability (MI) are obtained in terms of $H$ and the positive to negative ion density ratio $\beta$. The growth rate of MI is obtained, the maximum value of which increases with $\beta$ and decreases with $H$. The results could be important for understanding the origin of modulated QIAW packets in the environments of dense astrophysical objects, laboratory negative ion plasmas as well as for the next generation laser solid density plasma experiments.