Study of Magneto-Transmission Spectra of La$_{0.7}$Pb $_{0.3}$MnO$_{3 - \delta}$ Epitaxial Thin Film

Magneto-transmission (MT) of epitaxially grown La
_0.7
Pb
_0.3
MnO
_3-delta
as measured and studied. ThermoElectron Nexus 670 FT-IR spectrometer equipped with an electromagnet was used to obtain IR spectra in the range of 350 to 4000 cm
^-1
in various applied magnetic fields up to 1.0 Tesla. For optimal magneto-spectroscopic measurements in transmission, the studied film had a thickness of 190 nm, with a maximum value up to 80% at 320 K in the colossal magneto-resistance (CMR) effect in 5.5 Tesla. It was observed that the MT peaks at around 1400 cm
^-1
with a maximum value of 1.0% at 1.0 Tesla. When compared with the CMR effect, the measured MT value at this peak position resembles that of the CMR effect closely in the field range studied