arXiv2014
In [1], a generalized type of Darboux transformations defined in terms of a twisted derivation was constructed in a unified form. Such twisted derivations include regular derivations, difference operators, superderivatives and $q$-difference operators as special cases. The formulae for the iteration of Darboux transformations are expressed in terms of quasideterminants. This approach not only enables one to recover the known Darboux transformations and quasideterminant solutions to the noncommutative KP equation, the non-Abelian two-dimensional Toda lattice equation, the non-Abelian Hirota-Miwa equation and the super KdV equation, but also inspires us to investigate quasideterminant solutions to $q$-difference soliton equations. In this paper, we first derive the bilinear B\"acklund transformations for the known bilinear $q$-difference two-dimensional Toda lattice equation ($q$-$2$DTL), then derive a Lax pair whose compatibility gives a new nonlinear $q$-$2$DTL equation and finally obtain its quasideterminant solutions by iteration of its Darboux transformations.