X-ray Irradiation-induced Carrier Doping Effects in Organic Dimer-Mott Insulators

T. Sasaki; H. Oizumi; N. Yoneyama; N. Kobayashi; N. Toyota

doi:10.1143/JPSJ.76.123701

paper

X-ray Irradiation-induced Carrier Doping Effects in Organic Dimer-Mott Insulators

arXiv:0710.3005 · doi:10.1143/JPSJ.76.123701

Abstract

We report X-ray irradiation-induced carrier doping effects on the electrical conductivity in the organic dimer-Mott insulators $κ$ -(ET) $_{2}$ $X$ with $X =$ Cu[N(CN) $_{2}$ ]Cl and Cu $_{2}$ (CN) $_{3}$ . For $κ$ -(ET) $_{2}$ Cu[N(CN) $_{2}$ ]Cl, we have observed a large decrease of the resistivity by 40 % with the irradiation at 300 K and the metal-like temperature dependence down to about 50 K. The irradiation-induced defects expected at the donor molecule sites might cause a local imbalance of the charge transfer in the crystal. Such molecular defects result in the effective doping of carriers into the half-filled dimer-Mott insulators.

4 pages, 3 figures

References in corpus (1)

The Dependence of the Superconducting Transition Temperature of Organic Molecular Crystals on Intrinsically Non-Magnetic Disorder: a Signature of either Unconventional Superconductivity or Novel Local Magnetic Moment Formation