Ultrafast photoinduced reflectivity transients in doped manganite Available to Purchase

The temperature and magnetic field dependence of ultrafast photoinduced spin and quasiparticle relaxation dynamics is reported in $La0.67Ca0.33MnO3$ and $LaMnO3$ single crystals and thin films. Both manganites reveal an unusually slow (∼10 μs) carrier relaxation process attributed to the spin-lattice relaxation in localized states. The quasiparticle dynamics is governed by the temperature- and magnetic field-dependent pseudogap in $La0.67Ca0.33MnO3,$ and by the temperature-independent Jahn–Teller gap in $LaMnO3.$ The loss of spectral weight near the Fermi level in $La0.67Ca0.33MnO3$ strongy affects the quasiparticle relaxation dynamics as temperature increases from below $TC.$ Our results show that the coupled dynamics of charge, spin and lattice is strongly correlated with the distinct gap structures in these manganites.