I propose to change the sign of the dilaton in the infrared~(IR) soft-wall
AdS/QCD model, in order to implement confinement. The deformed model exhibits
interesting properties, especially in describing chiral symmetry breaking. The
expectation value of the scalar field $X$, which determines the quark mass and
condensate, approaches a constant in the IR limit, rather than blows up in the
original model. In contrast to the estimate in Ref. \cite{Shifman:2007xn}, this
kind of solution will not lead to chiral symmetry restoration for
highly-excited states, due to the property of the harmonic-oscillator equation.
Instead, it will guarantee the Regge behavior of the axial meson spectrum, and
also the pseudoscalar mesons. The value of the condensate can be fixed by
requiring that the pion be massless in the chiral limit, but only under some
approximation in the present model. We also find that, by relaxing the IR
boundary conditions, the unphysical massless state in the vector channel can be
eliminated.Comment: A modification of the boundary condition is proposed to eliminate the
unphysical "pion" mode. Version to appear in Physical Review