Photorefractive two-beam coupling was performed in fullerene C_(60)-doped nematic liquid crystal cell. Photorefractive gain coefficient as high as 1386 cm~(-1) was obtained at an input pump power as weak as 16 mW. However, the thin film nature led to a small gain of 16. By the use of several such cells stacked together to increase the overall interaction length, the optical gain was improved greatly, and the pump power to obtain the highest optical gain was reduced. At 1.2 V, the highest gain of 141 was obtained for the 40 μW signal at an input pump power of 12 mW.
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