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Durham University

Institute of Medieval and Early Modern Studies (IMEMS)

Staff and Governance

Core Staff

The day-to-day running of IMEMS is the responsibility of the Core Executive Committee, comprising the Director and Associate Directors and the Administrator. 

Publication details for Prof Brian Tanner

Buchanan, J. D. R., Hase, T. P. A., Tanner, B. K., Hughes, N. D. & Hicken, R. J. (2002). Determination of the thickness of Al2O3 barriers in magnetic tunnel junctions. Applied Physics Letters 81(4): 751-753.

Author(s) from Durham


The barrier thickness in magnetic spin-dependent tunnel junctions with Al2O3 barriers has been measured using grazing incidence x-ray reflectivity and by fitting the tunneling current to the Simmons model. We have studied the effect of glow discharge oxidation time on the barrier structure, revealing a substantial increase in Al2O3 thickness with oxidation. The greater thickness of barrier measured using grazing incidence x-ray reflectivity compared with that obtained by fitting current density-voltage to the Simmons electron tunneling model suggests that electron tunneling is localized to specific regions across the barrier, where the thickness is reduced by fluctuations due to nonconformal roughness.


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Full Executive Committee

Our Full Executive Committee is made up of the Core Executive Committee, listed above, plus a number of executive members including:

International Advisory Board

We are extremely fortunate to have be able to call on the help and guidance of colleagues from around the world who help to shape and guide our direction, strategy and international reach. Our current Advisory Board members are: