Photonic Band Gap Enhanced Energy Transfer in Eu$^{3+}$ Doped TbPO$_{4 }$ Inverse Opal

Photoluminescence (PL) of Eu$^{3+}$ doped TbPO$_{4}$(TbPO$_{4}$: Eu) inverse opal photonic crystals was investigated. The results showed that the energy transfer from the donor Tb$^{3+}$ to the acceptor Eu$^{3+ }$can be enhanced effectively by the photonic bandgaps in the photonic crystals. When the fluorescence emission wavelength of the donor Tb$^{3+}$ overlapped the photonic band gap, the fluorescence intensity of the donor was suppressed, while the fluorescence intensity of the acceptor Eu$^{3+ }$was obviously enhanced. This enhancement can be attributed to the inhibition of radiative emission of donor in the inverse opal photonic crystals.