Measurements of the Einstein relation in doped and undoped molecular thin films

Rapid Communication

Measurements of the Einstein relation in doped and undoped molecular thin films

O. Tal, I. Epstein, O. Snir, Y. Roichman, Y. Ganot, C. K. Chan, A. Kahn, N. Tessler, and Y. Rosenwaks

Phys. Rev. B 77, 201201(R) – Published 2 May 2008

Abstract

We present the Kelvin probe force microscopy measurements of the Einstein relation, i.e., the relation between the diffusion coefficient of charge carriers and their mobility, in undoped and doped disordered organic thin films. The theoretical prediction of a large deviation of the Einstein relation from its classical value is verified and attributed to the energy distribution of the density of states. The results are explained in the context of degeneracy effects on the transport in disordered organic thin films, and their implications for organic-based devices are discussed.

Received 13 February 2008

DOI:https://doi.org/10.1103/PhysRevB.77.201201

Authors & Affiliations

O. Tal^1,*, I. Epstein¹, O. Snir¹, Y. Roichman^2,†, Y. Ganot², C. K. Chan³, A. Kahn³, N. Tessler², and Y. Rosenwaks¹

¹School of Electrical Engineering-Physical Electronics, Tel Aviv University, Tel Aviv 69978, Israel
²Department of Electrical Engineering, Technion Israel institute of Technology, Haifa 32000, Israel
³Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA

^*Present address: Leiden Institute of Physics, Leiden University, 2300 RA Leiden, Netherlands.
^†Present address: Department of Physics, New York University, New York 10003, USA.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 77, Iss. 20 — 15 May 2008

Reuse & Permissions

Access Options

Author publication services for translation and copyediting assistance advertisement

Physical Review B

covering condensed matter and materials physics