  We study spin chirality for a spin-1/2 zigzag XY chain at low temperature by
applying a low-temperature density-matrix renormalization group technique. We
calculate temperature dependence of dynamical and static correlations of the
chirality. In a chiral phase, chiral long-range order at zero temperature
disappears at finite temperature, consistent with the fact that there is no
long-range order at finite temperature in one-dimensional systems with
short-range interactions. In a dimer phase next to the chiral phase, we find an
enhancement of static chiral correlation as well as spin correlation with
increasing temperature. The enhancement corresponds to the increase of spectral
weight inside a gap in the dynamical chiral-correlation function. This
temperature-induced chiral correlation is a demonstration of the presence of a
chiral state in excited states.
