Magnetic Field-Induced Lattice Effects in a Quasi-2D Organic Conductor Close to the Mott Metal-Insulator Transition

Abstract

We present ultra-high-resolution dilatometric studies in magnetic fields on a quasi-two-dimensional organic conductor $\kappa$-(D8-BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br, which is located close to the Mott metal-insulator (MI) transition. The obtained thermal expansion coefficient, $\alpha (T)$, reveals two remarkable features: (i) the Mott MI transition temperature $T_{MI}$ = (13.6 $\pm$ 0.6)\,K is insensitive to fields up to 10\,T, the highest applied field; (ii) for fields along the interlayer \emph{b}-axis, a magnetic-field-induced (FI) phase transition at $T_{FI}$ = (9.5 $\pm$ 0.5)\,K is observed above a threshold field $H_c\sim$ 1 T, indicative of a spin reorientation with strong magneto-elastic coupling.

5 pages, 4 figures

References in corpus (3)

• Unconventional critical behaviour in a quasi-two-dimensional organic conductor
• Anomalous Lattice Response at the Mott Transition in a Quasi-2D Organic Conductor
• Scaling theory of the Mott transition and breakdown of the Grüneisen scaling near a finite-temperature critical end point

Cited by in corpus (1)

• Probing the Mott Physics in $\kappa$-(BEDT-TTF)${}_2$X Salts via Thermal Expansion