On the existence of ion-acoustic double layers in negative-ion plasmas

• DOI: 10.1017/s0022377800016093
• Publication Date: 2009-03-17T12:19:45Z
• Authors: S. Baboolal; R. Bharuthram; M. A. Hellberg

It is well known that ion-acoustic double layers occur in plasmas containing two-temperature electron species and positive ions. In a recent study Verheest suggested such structures can when there only one but both negative ion species. There stationary modified Korteweg de Vries equation was derived to support his deduction. This prediction, however, contradicts our own arbitrary-amplitude studies, which also cover the parameter regime. Here we resolve discrepancy by examining approaches pseudo-potential formulation more relevant detail. The implications of this extend beyond realm present subject.