Abstract

Using a cw Ar⁺ laser at 488 nm, photoinduced short-circuit currents and open-circuit voltages have been measured in a self-pumped¹ BaTiO₃ crystal. The crystal, when pumped as shown in Fig. 1(a), produces voltages and currents along the c axis when the laser is turned on and off [Fig. 1(b)]. Initial fields of up to 200 V/cm are created by the pyroelectric effect² which induces temperature gradients throughout the crystal. The absorption coefficient α at 488 nm for e- and o-polarized light in our crystal was measured to be 1.2 and 2.0 cm^-1, respectively. Constant short-circuit pyroelectric current densities vary linearly with laser intensity and can reach values of 10 nA/cm². The measured pyroelectric constant for e-polarized pumping of the crystal is 6.6 nA/W and 15% smaller for o-ray pumping (Fig. 2).

© 1986 Optical Society of America