Enhancement of the¹H NMR Relaxation Rate at Low Temperatures and Development of Antiferromagnetic Spin Fluctuations of π-Electrons in Superconducting λ-(BETS)₂GaCl₄

Multifunctional interplay among the conductivity, magnetism and dielectricity in π–d interacting λ-(BETS)2FeCl4

“…) It is noted that the band-structure calculations [28] give a peak of the staggered electronic susceptibility around q AF ¼ (0, p/c) that corresponds to the 2k F vector spanning two open Fermi surfaces. This is consistent with 77 Se-and 1 H NMR measurements on the superconducting GaCl 4 salt which reveal an existence of strong AFM spin fluctuations in its normal state [37,38], because the GaCl 4 salts can be iso-electronic to the FeCl 4 salt.…”

“…As already mentioned in Section 3.1, a significant enhancement of spinelattice relaxation rate 1/(T 1 T) is observed in the metallic state below 24 K by 1 H NMR studies [37]. This enhancement is interpreted as a development of AFM spin fluctuations that may be caused by a correlation effect of strong dimerization at A along the column (Section 2).…”

Evidence of antiferromagnetic fluctuation in the unconventional superconductor λ -(BETS) 2GaCl4 by CKobayashi1, Kawamoto2 2017Phys. Rev. B265260View full textAdd to dashboardCite

“…1 H and 77 Se NMR measurements have been performed previously, but several results appear contradictory. An increase in 1/T 1 T was observed below 25 K in 1 H NMR [11], but the 77 Se NMR experiment suggested that 1/T 1 T is constant or weak temperature dependent below 70 K [12,13]. Moreover, the linewidths of 77 Se NMR using randomly oriented samples and single-crystal samples show the different behaviors at low temperatures [12,13].…”