Iterative reconstruction of magnetic induction using Lorentz transmission electron tomography.

Ultramicroscopy

PubMedID: 25528453

Phatak C, Gürsoy D. Iterative reconstruction of magnetic induction using Lorentz transmission electron tomography. Ultramicroscopy. 2014;150C54-64.
Intense ongoing research on complex nanomagnetic structures requires a fundamental understanding of the 3D magnetization and the stray fields around the nano-objects. 3D visualization of such fields offers the best way to achieve this. Lorentz transmission electron microscopy provides a suitable combination of high resolution and ability to quantitatively visualize the magnetization vectors using phase retrieval methods. In this paper, we present a formalism to represent the magnetic phase shift of electrons as a Radon transform of the magnetic induction of the sample. Using this formalism, we then present the application of common tomographic methods particularly the iterative methods, to reconstruct the 3D components of the vector field. We present an analysis of the effect of missing wedge and the limited angular sampling as well as reconstruction of complex 3D magnetization in a nanowire using simulations.