Home >  Conference > Condenced Matter Informal Seminar: Toward unified physics of quasi-one-dimensional organic superconductors: (TMTTF)2X in the metallic state (X=Br)

Condenced Matter Informal Seminar: Toward unified physics of quasi-one-dimensional organic superconductors: (TMTTF)2X in the metallic state (X=Br)

Date : Monday, February 27th, 2017 4:00 pm - 5:00 pm Place : Seminar Room 2 (A612), 6th Floor, ISSP Lecturer : Prof. Woun Kang Affiliation : Ewha Womans University, Seoul, Korea Language in Speech : Japanese

(TMTTF)2X is the sulfur analog of the well-known quasi-one-dimensional (Q1D) organic superconductor (TMTSF)2X and precedes it in the development of organic metals. Although they are metallic at room temperature, they undergo transitions into various insulating states at low temperature. While the insulating states deserved intensive study by themselves, efforts have been made to bring (TMTTF)2X to a metal at low temperature and to find superconductivity therein. Over a period of 14 years, superconductivity was confirmed in four members of (TMTTF)2X such as X=Br, PF6, AsF6, SbF6 under relatively high pressure. On the other hand, a generic phase diagram has been proposed to assume that the physics of the selenium and sulfur series must be treated on an equal footing. In an effort to support this idea, there has been a number of attempts to verify if the metallic state of (TMTTF)2X has indeed the same ingredients as those of (TMTSF)2X, but without much success until recently. In this study, we chose (TMTTF)2Br for a practical reason and studied the angular dependent magnetoresistance oscillations (AMRO) and the Hall effect under high pressure. Two of the most representative properties of Q1D metals, three-dimensional AMRO oscillations (including Lebed resonances, Danner-Chaikin oscillations, and the third angle effect) and field-induced spin-density-waves accompanied with quantized Hall resistance, were unambiguously confirmed in (TMTTF)2X in the end. These results suggest that physics of Q1D electronic system is universal regardless of the sulfur and selenium series.


(Published on: Thursday February 23rd, 2017)