2024-03-28T12:45:29Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/479592022-11-17T02:08:08Zhdl_2115_20057hdl_2115_148Time-Resolved Photoresponse Measurements of the Electrical Conductivity of the Quasi-Two-Dimensional Organic Superconductor β-(BEDT-TTF)2I3 Using a Nanosecond Laser PulseIimori, ToshifumiSabeth, FarzanaNaito, ToshioOhta, Nobuhiro431Time-resolved photoresponses in resistance have been measured following the nanosecond laser pulse excitation for the quasi-two-dimensional organic superconductors of hydrogenated and deuterated β-(BEDT-TTF)2I3 [BEDT-TTF = bis-(ethylenedithio)tetrathiafulvalene], which show two different superconducting states with high-Tc and low-Tc at temperatures near the critical temperatures. A transient increase of the resistance is induced by photoirradiation at all the temperatures, but a marked temperature dependence of the decay time is observed at temperatures close to the high-Tc phase transition temperature; the decay rate becomes faster and then becomes constant in both compounds, as the temperature decreases across the high-Tc phase transition temperature. The temperature dependence of the photoresponse intensity is different from the one expected from the bolometric effects, indicating the presence of the nonbolometric photoresponse. A possible mechanism explaining the photoresponse of the conductivity is discussed, based on the isotope effect on the photoresponse. A comparison is also made between β-(BEDT-TTF)2I3 and κ-(BEDT-TTF)2Cu[N(CN)2]Br for the transient photoresponse in resistance at temperatures across the metal-superconductor phase transition temperature.American Chemical SocietyJournal Articleapplication/pdfhttp://hdl.handle.net/2115/47959https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/47959/1/JPCC115-48_23998-24003.pdf1932-7447Journal of Physical Chemistry C1154823998240032011-12-08enginfo:doi/10.1021/jp2088912publisher