Surface and intrinsic low frequency conductivity of KTiOPO4 (KTP) in the temperature range 290 – 1100 K

Abstract

The ac conductivity and dielectric function of KTiOPO4 were measured in the frequency range from 10 Hz to 10 MHz and in the temperature range from 290 to 1100 K, using Au evaporated contacts. Strong low frequency relaxation after field annealing experiments up to 600–1100K is observed, which can be attributed to surface segregation. Conclusively, by removal of the surface layers, intrinsic low frequency behavior is retained. The conductivity spectra indicate a power law behavior σ(ω) ∼ ωs with a quite small exponent s⋍0.17. This dependence is possibly caused by the one dimensional character of AC conductivity.