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

The photocarrier mobility of Fe 0.03 wt%-doped potassium lithium tantalate niobate (K0.95Li0.05Ta0.61Nb0.39O3) was investigated by time-of-flight (TOF) measurement. The longitudinal photocarrier response due to pulsed excitation leads to values of the drift mobility of μh = 1.45 × 10−2 cm2/V s for holes, μe = 0.325 × 10−2 cm2/V s for electrons, and a value for the range of holes (μτ)h = 4.38 × 10−5 cm2/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.