Enhanced superconducting and spin-density-wave ordering temperatures of gated quasi-one-dimensional organic superconductors

Presented are the results of calculations suggesting that the quasi-one-dimensional organic superconductors (TMTSF)2 X (where TMTSF represents tetramethyltetraselenafulvalene and X is P F6 As F6, Cl O4, etc.) may show a substantial increase in their superconducting and spin-density-wave ordering temperatures when the Fermi level is raised through application of an electrostatic gating voltage. A rich behavior is observed, strongly dependent on the form of the superconducting order parameter, as the Fermi level approaches the Van Hove singularity at ka =0. Included are predictions for the behavior of these materials under zero and moderate applied pressure. It is found that TSDW as high as 50 K and superconducting Tc as high as 20 K may be achieved at optimal gate voltages of approximately 100 mV.