Luminescence of LuCl$_3$ Doped With Pr$^{3+}$

The optical properties of Pr
³⁺
activated LuCl
₃
under intra-ionic 4f
²
rarr 4f
¹
5d
¹
and band gap (lambda
_ex
= 193 nm; X-ray) excitations has been evaluated. The luminescence of LuCl
₃
:Pr
³⁺
is found to be strongly dependent on the excitation energy: for energies less than the absorption edge of the host, the luminescence of LuCl
₃
: Pr
³⁺
is dominated by the 4f
¹
5d
¹
rarr 4f
²
interconfigurational optical transitions. When luminescence is excited by photons with energies corresponding to the absorption edge or the band gap of the host, the emission spectrum is dominated by the intraconfigurational 4f
²
rarr 4f
²
optical transitions, which emanate from the Pr
³⁺
3P
_J
states. The luminescence efficiency of the inter- and intraconfigurational optical transitions is high at room temperature. A model to account for the dependence of the emission behavior of Pr
³⁺
ion on the excitation energy is presented.