Photocarrier transport in iron-doped potassium lithium tantalate niobate studied by time-of-flight measurement

Abstract

The photocarrier mobility of Fe 0.03 wt%-doped potassium lithium tantalate niobate (K 0.95Li 0.05Ta 0.61Nb 0.39O 3) was investigated by time-of-flight (TOF) measurement. The longitudinal photocarrier response due to pulsed excitation leads to values of the drift mobility of μ h = 1.45 × 10 −2 cm 2/V s for holes, μ e = 0.325 × 10 −2 cm 2/V s for electrons, and a value for the range of holes ( μτ) h = 4.38 × 10 −5 cm 2/V at room temperature and at low field 3 KV/cm. The response time of holes and electrons (or the relaxation time) is determined to be 3.02 × 10 −3 s and 3.74 × 10 −3 s, respectively. The mobility of holes strongly depends on the field strength, and is observed to decrease with increasing bias field.