Nonvolatile holographic storage in triply doped LiNbO₃: Hf, Fe, Mn crystals

LiNbO₃:Fe, Mn crystal has been suggested to be used for solving the problem of information volatility during the read-out process with all-optical facilities, but the minute order response time is far from the requirements for the real-time information processing. We present the nonvolatile holographic storage properties of LiNbO₃:Hf, Fe, Mn. The response time is shortened to 5.0 s, and the sensitivity S' is enhanced to 0.22 cm/J in this triply doped crystal. The experimental results show that the HfO₂ doping threshold is 5.0 mol.%. Thus it seems that we have found a useful tetravalent dopant for LiNbO₃:Fe, Mn that can obviously improve the nonvoaltile holographic recording sensitivity.