Exciton creation in LuAlO3 single crystalline film

Single crystalline films (SCF) of LuAP attract attention because of the perspective of its application as 2D screens for X‐ray registration with high spatial resolution. An intensive sharp reflectivity peak at the edge of the fundamental absorption region with maximum at 8.37 eV at 10 K was found for a series of LuAP SCF grown by liquid phase epitaxy on YAP substrate. The dependence of the peak maximum and profile on temperature demonstrates its exciton origin. The absorption spectrum was calculated from reflectivity using Kramers–Kronig relations; the bandgap value was determined for LuAP as Eg = 8.44 eV at 10 K. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)