Zobrazeno 1 - 10
of 164
pro vyhledávání: '"Straessler, S."'
Publikováno v:
Phys. Rev. B 71, 064201 (2005)
A vast class of disordered conducting-insulating compounds close to the percolation threshold is characterized by nonuniversal values of transport critical exponent t, in disagreement with the standard theory of percolation which predicts t = 2.0 for
Externí odkaz:
http://arxiv.org/abs/cond-mat/0503647
Publikováno v:
Appl. Phys. Lett. vol.83, pag.189 (7 July 2003)
We propose a model of transport in thick-film resistors which naturally explains the observed nonuniversal values of the conductance exponent t extracted in the vicinity of the percolation transition. Essential ingredients of the model are the segreg
Externí odkaz:
http://arxiv.org/abs/cond-mat/0307141
Publikováno v:
Phys. Rev. B vol.68, 024207 (2003)
We propose a theory of the origin of transport nonuniversality in disordered insulating-conducting compounds based on the interplay between microstructure and tunneling processes between metallic grains dispersed in the insulating host. We show that
Externí odkaz:
http://arxiv.org/abs/cond-mat/0306665
We re-analyse earlier measurements of resistance R and piezoresistance K in RuO2-based thick-film resistors. The percolating nature of transport in these systems is well accounted by values of the transport exponent t larger than its universal value
Externí odkaz:
http://arxiv.org/abs/cond-mat/0212319
Percolating networks based on interparticle tunneling conduction are shown to yield a logarithmic divergent piezoresistive response close to the critical point as long as the electrical conductivity becomes nonuniversal. At the same time, the piezore
Externí odkaz:
http://arxiv.org/abs/cond-mat/0211133
A number of evidences suggests that thick-film resistors are close to a metal-insulator transition and that tunneling processes between metallic grains are the main source of resistance. We consider as a minimal model for description of transport pro
Externí odkaz:
http://arxiv.org/abs/cond-mat/0203612
The piezoresistive response of granular metals under uniaxial strain is strongly dependent on the concentration of the conducting phase. Here we show that the piezoresistive anisotropy is reduced as the system approaches its percolation thresold, fol
Externí odkaz:
http://arxiv.org/abs/cond-mat/0203557
The validity of some experimental data on which the paper was based have been questioned by the report of the Committee of the Bell Labs released on September 2002.
Externí odkaz:
http://arxiv.org/abs/cond-mat/0201334
Publikováno v:
Phys. Rev. Lett. vol.85, p.4771 (27 nov. 2000)
We show the intrinsic inconsistency of the conventional phonon mediated theory of superconductivity in relation to the observed properties of Rb$_3$C$_{60}$. The recent, highly accurate measurement of the carbon isotope coefficient $\alpha_{\rm C}=0.
Externí odkaz:
http://arxiv.org/abs/cond-mat/0105560
The evidence for the key role of the $\sigma$ bands in the electronic properties of MgB$_2$ points to the possibility of nonadiabatic effects in the superconductivity of these materials. These are governed by the small value of the Fermi energy due t
Externí odkaz:
http://arxiv.org/abs/cond-mat/0105351