Energy scales for electronic noise processes in the quasi-two-dimensional organic Mott system $κ$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl
| dc.creator | Mueller, Jens | |
| dc.creator | Brandenburg, Jens | |
| dc.creator | Schlueter, John A. | |
| dc.date | 2009-03-18 | |
| dc.date.accessioned | 2026-07-07T12:53:38Z | |
| dc.date.available | 2026-07-07T12:53:38Z | |
| dc.description | Resistance noise spectroscopy is applied to bulk single crystals of the quasi-two-dimensional organic Mott insulator $κ$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl both under moderate pressure and at ambient-pressure conditions. When pressurized, the system can be shifted to the inhomogeneous coexistence region of antiferromagnetic insulating and superconducting phases, where percolation effects dominate the electronic fluctuations [J. Müller {\it et al.}, Phys. Rev. Lett. {\bf 102}, 047004 (2009)]. Independent of the pressure conditions, at higher temperatures we observe generic $1/f^α$-type spectra. The magnitude of the electronic noise is extremely enhanced compared to typical values of homogeneous semiconductors or metals. This indicates that a highly inhomogeneous current distribution may be an intrinsic property of organic charge-transfer salts. The temperature dependence of the nearly $1/f$ spectra can be very well described by a generalized random fluctuation model [Dutta, Dimon, and Horn, Phys. Rev.\ Lett. {\bf 43}, 646 (1979)]. We find that the number of fluctuators and/or their coupling to the electrical resistance depends on the temperature, which possibly relates to the electronic scattering mechanisms determining the electrical resistance. The phenomenological model explains a pronounced peak structure in the low-frequency noise at around 100 K, which is not observed in the resistivity itself, in terms of the thermally-activated conformational degrees of freedom of the ET molecules' ethylene endgroups. | |
| dc.identifier | https://arxiv.org/abs/0903.3197 | |
| dc.identifier | http://arxiv.org/abs/0903.3197 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/223690 | |
| dc.subject | Superconductivity | |
| dc.title | Energy scales for electronic noise processes in the quasi-two-dimensional organic Mott system $κ$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl | |
| dc.type | text |