Inclusion of a quantizing magnetic field in a partially degenerate plasma has interesting effects on the propagation of solitary and nonlinear periodic structures in coupled kinetic Alfven acoustic waves. In this paper we use the two potential theory and investigate the nonlinear structures using Sagdeev potential approach and further analyze it using nonlinear dynamical methods. It is shown that the existence of solitary structure is sensitive to small temperature effects and quantizing magnetic field in a dense plasma with adiabatically trapped electrons. The work presented here is useful in understanding the low frequency wave propagation in a dense astrophysical environment like white dwarf stars and in low beta laboratory plasmas e.g. intense laser-plasma interactions.