PRESSURE EFFECT ON CONDUCTIVITY IN Au(dmit)_2 LANGMUIR-BLODGETT FILMS

摘要

The resistance of the Langmuir-Blodgett films of ditetradecyldimethylammonium-Au(dmit)_2 (2C_(14)-Au(dmit)_2) salt has been measured under hydrostatic pressure up to 0.7 GPa. The room-temperature resistance decreases with increasing pressure, reaching a 0.6-times smaller value compared to that at ambient pressure. The film under the pressure shows a clear resistance decrease below 1.4 K on cooling, while that under ambient pressure shows a blunt decrease below 0.85 K and it turns to increase below 0.65 K. These results suggest the existence of the pressure-induced superconducting phase together with the earlier results of the ac magnetic susceptibility measurement.