**
A. C. Jacko ^{1}, J. O. Fjearestad ^{2}, and B. J. Powell ^{1}**

^{1}Centre for Organic Photonics and Electronics, School of Mathematics and Physics, University of Queensland, QLD 4072, Australia

^{2}School of Mathematics and Physics, University of Queensland, QLD 4072, Australia Email: bjpowell@gmail.com

Discoveries of ratios whose values are constant within broad classes of materials have led to many deep physical insights. The Kadowaki-Woods ratio^{1} compares the temperature dependence of a metal’s resistivity to that of its heat capacity; thereby probing the relationship between the electron-electron scattering rate and the renormalisation of the electron mass. However, the Kadowaki-Woods ratio takes very different values in different materials^{2}. We recently introduced a ratio, closely related to the Kadowaki-Woods ratio, that includes the effects of carrier density and spatial dimensionality and takes the same (predicted) value in organic charge transfer salts, transition metal oxides, heavy fermions and transition metals - despite the numerator and denominator varying by ten orders of magnitude.^{3} Hence, in these materials, the same emergent physics is responsible for the mass enhancement and the quadratic temperature dependence of the resistivity and no exotic explanations of their Kadowaki-Woods ratios are required.

This work supported by the the Australian Research Council's (ARC) Discovery Projects funding scheme (project DP0878523). B.J.P. is the recipient of an ARC Queen Elizabeth II Fellowship (DP0878523).

[1] M. J. Rice, Phys. Rev. Lett. 20, (1968) 1439; K. Kadowaki & S. B. Woods, Solid State Commun. 58, (1986) 507.

[2] N. E. Hussey, J. Phys. Soc. Japan 74, (2005) 1107; M. Dressel, G. Grüner, J. E. Eldridge & J. M. Williams, Synth. Met. 85, (1997) 1503.

[3] A. C. Jacko, J. O. Fjaerestad & B. J. Powell, Nature Phys. 5, 422 (2009).

**
**

View poster as pdf.