Home Page of A. Lodder

Prof. dr. Adri Lodder

Adri Faculteit der Exacte Wetenschappen/Natuurkunde en Sterrenkunde
Vrije Universiteit
De Boelelaan 1081
1081 HV Amsterdam
The Netherlands

tel. (31) 20 - 59 87837
e-mail: A.Lodder@few.vu.nl, and: adrilodder@msn.com
FAX (31) 20 - 59 87999

In real life:
Adri Lodder
Amstelveenseweg 749
1081 JE Amsterdam
tel. 020 - 6424567

Full Professor in Condensed Matter Theory.
Since April 2004 Professor Emeritus, after having given his valedictory address, entitled "The Truth is the Issue".

Subjects:
Electromigration in dilute alloys.
Superconductivity in dirty and cleaner mesoscopic structures.
He published over hundred papers.

Dr. Adri Lodder is Professor Emeritus in Condensed Matter Theory. He is an expert in studying and calculating electronic properties in dilute alloys. All calculations made are of the ab initio type. This means that the properties are calculated starting from the basic information of the constituent atoms, namely their charge and mass. For the metals only the lattice structure is required.

He developed a description through which it became possible to account for charge transfer and lattice distortion effects at and around an impurity in a metallic host. He applied this theory in order to explain life times of electrons due to scattering by hydrogen in the interstitial alloy Pd(H) measured in the group of Professor Ronald Griessen. He was able to describe electromigration forces on hydrogen in the interstitial alloys V(H), Nb(H) and Ta(H) measured by A.H. Verbruggen in Griessen's group.
Adri

From 1991 to 2003 he also contributed to the theory of superconductivity, applied to dirty superconductor/normal metallic (S/N) multilayers and to clean SNS junctions, including junctions in which the N part has a constriction. Part of the latter work he did in collaboration with Yu.V. Nazarov.

With his PhD students J. van Ek and J.P. Dekker he made an impressive contribution to the calculation of the electromigration wind force on impurities and around vacancies in dilute interstitial and substitutional alloys. These calculations in fact introduced a new state of the art, in that all important electronic effects could be accounted for, by which all metals of interest in the Periodic System could be dealt with.
In addition he contributed to the understanding of the magnitude of the direct electromigration force on the hydrogen, by that getting involved in a long standing controversy. This controversy was initiated in 1962 by the prediction of Bosvieux and Friedel, that that force is completely screened out and that only a wind force is operative. In 2005 he succeeded to find a fatal error in the 1962-paper, by that resolving the controversy for a great deal. This result was published in Europhysics Letters 72 (2005) 774, which paper carries the title "Electromigration theory unified". In addition, the paper published in Physical Review B74 (2006) 045111 presents a new simplified formulation of electromigration theory. Finally, in September 2006 he falsified the supporting claim of a complete screening, published in 1975 by Turban, Nozières and Gerl. The on 26 October 2006 submitted manuscript carries the intriguing title "The Direct Force Controversy in Electromigration Exit". By now it has been published in Defect and Diffusion Forum 261-262 (2007) 77. Recently a collaboration started with Professor Istvan Nagy in Budapest, which has led to the paper "Description of a migrating proton embedded in an electron gas". In this work a selfconsistent potential is used for the proton. Finally, in January 2010, the following paper "Electromigration force on a proton with a bound state" has been published. In this paper it has been shown explicitly, that the direct valency Zd of a proton surrounded by a bound electron becomes negative, while just a screening electron which is effectively free corresponds to a Zd > 0.8. By this the old controversy regarding the magnitude of Zd has become part of the past. This holds the more so as Nozières has sent an email with the message, that, based on his own model calculation, he had to confess that, unfortunately, he and Friedel were wrong thirty years ago!



The picture, here on the right, was taken on the occasion of his farewell, which led to an interview for the University News Paper Ad Valvas. It was published in the issue of 24 May 2004.