PULSE-PROPAGATION OF ACCUMULATED PHOTON-ECHOES IN ND3-DOPED SILICATE GLASS-FIBER( ION)

Pulse-propagation phenomena of accumulated photon echo signals was inv estigated for the F-4(3/2)(1)-I-4(9/2) transition of the Nd3+ ion dope d with 20 ppm concentration in silicate glass fiber (core diameter of 6 mu m) at 4.2 K using an 82 MHz mode-locked dye laser. The intensity of the transmitted probe pulses from the Nd3+ fiber was measured as a function of the Nd3+ fiber length. The fiber length for the maximum pr obe-pulse intensity induced by the pump pulses was determined to be 4 m when the pump pulses of 0.50 mW average power and the probe pulses o f 0.25 mW average power were used. We derived the pulse area equations which take into account the coherent interaction between the pulses a nd the Nd3+ fiber. The fiber-length dependence of the signal intensity was explained well by the pulse area equations. (C) 1997 American Ins titute of Physics.