Novel Advances in Sub-Nanometer Imaging

A quantum mechanical exploration of phonon energy-loss spectroscopy using electrons in the aloof beam geometry

LJ Allen, HG Brown, SD Findlay, BD Forbes

2018-03-01

Phonon energy-loss spectroscopy using electrons has both high resolution and low resolution components, associated with short- and..

Atomic resolution elemental mapping using energy-filtered imaging scanning transmission electron microscopy with chromatic aberration correction

FF Krause, A Rosenauer, J Barthel, J Mayer, K Urban, RE Dunin-Borkowski, HG Brown, BD Forbes, LJ Allen

2017-10-01

This paper addresses a novel approach to atomic resolution elemental mapping, demonstrating a method that produces elemental maps ..

Simulation in elemental mapping using aberration-corrected electron microscopy

LJ Allen

2017-09-01

Elemental mapping at the atomic scale in aberration-corrected electron microscopes is becoming increasingly widely used. In this p..

Composition measurement in substitutionally disordered materials by atomic resolution energy dispersive X-ray spectroscopy in scanning transmission electron microscopy

Z Chen, DJ Taplin, M Weyland, LJ Allen, SD Findlay

2017-05-01

The increasing use of energy dispersive X-ray spectroscopy in atomic resolution scanning transmission electron microscopy invites ..

A new method to detect and correct sample tilt in scanning transmission electron microscopy bright-field imaging

HG Brown, R Ishikawa, G Sánchez-Santolino, NR Lugg, Y Ikuhara, LJ Allen, N Shibata

2017-02-01

Important properties of functional materials, such as ferroelectric shifts and octahedral distortions, are associated with displac..

Influence of experimental conditions on atom column visibility in energy dispersive X-ray spectroscopy

JH Dycus, W Xu, X Sang, AJ D'Alfonso, Z Chen, M Weyland, LJ Allen, SD Findlay, JM LeBeau

2016-12-01

Here we report the influence of key experimental parameters on atomically resolved energy dispersive X-ray spectroscopy (EDX). In ..

Practical aspects of diffractive imaging using an atomic-scale coherent electron probe

Z Chen, M Weyland, P Ercius, J Ciston, C Zheng, MS Fuhrer, AJ D'Alfonso, LJ Allen, SD Findlay

2016-10-01

Four-dimensional scanning transmission electron microscopy (4D-STEM) is a technique where a full two-dimensional convergent beam e..

Quantitative atomic resolution elemental mapping via absolute-scale energy dispersive X-ray spectroscopy

Z Chen, M Weyland, X Sang, W Xu, JH Dycus, JM LeBeau, AJ D'Alfonso, LJ Allen, SD Findlay

2016-09-01

Quantitative agreement on an absolute scale is demonstrated between experiment and simulation for two-dimensional, atomic-resoluti..

Modeling energy-loss spectra due to phonon excitation

BD Forbes, LJ Allen

2016-07-13

We discuss a fundamental theory of how to calculate the phonon-loss sector of the energy-loss spectrum for electrons scattering fr..

Structure retrieval with fast electrons using segmented detectors

HG Brown, AJ D'Alfonso, Z Chen, AJ Morgan, M Weyland, C Zheng, MS Fuhrer, SD Findlay, LJ Allen

2016-04-27

We introduce an algorithm for the reconstruction of the complex transmission function of a specimen using segmented detectors in s..

Dose-dependent high-resolution electron ptychography

AJ D'Alfonso, LJ Allen, H Sawada, AI Kirkland

2016-02-07

Recent reports of electron ptychography at atomic resolution have ushered in a new era of coherent diffractive imaging in the cont..

Addressing preservation of elastic contrast in energy-filtered transmission electron microscopy

HG Brown, AJ D'Alfonso, BD Forbes, LJ Allen

2016-01-01

Energy-filtered transmission electron microscopy (EFTEM) images with resolutions of the order of an Ångström can be obtained using..

Deterministic approaches to coherent diffractive imaging

LJ Allen, AJ D'Alfonso, AV Martin, AJ Morgan, HM Quiney

2015-11-24

In this review we will consider the retrieval of the wave at the exit surface of an object illuminated by a coherent probe from on..

Energy dispersive X-ray analysis on an absolute scale in scanning transmission electron microscopy

Z Chen, AJ D'Alfonso, M Weyland, DJ Taplin, LJ Allen, SD Findlay

2015-10-01

We demonstrate absolute scale agreement between the number of X-ray counts in energy dispersive X-ray spectroscopy using an atomic..

Optimal ADF STEM imaging parameters for tilt-robust image quantification

KE MacArthur, AJ D'Alfonso, D Ozkaya, LJ Allen, PD Nellist

2015-09-01

An approach towards experiment design and optimisation is proposed for achieving improved accuracy of ADF STEM quantification. In ..

Surface determination through atomically resolved secondary-electron imaging

J Ciston, HG Brown, AJ D'Alfonso, P Koirala, C Ophus, Y Lin, Y Suzuki, H Inada, Y Zhu, LJ Allen, LD Marks

2015-06-17

Unique determination of the atomic structure of technologically relevant surfaces is often limited by both a need for homogeneous ..

Accurate Nanoscale Crystallography in Real-Space Using Scanning Transmission Electron Microscopy

JH Dycus, JS Harris, X Sang, CM Fancher, SD Findlay, AA Oni, TTE Chan, CC Koch, JL Jones, LJ Allen, DL Irving, JM Le Beau

2015-04-30

Here, we report reproducible and accurate measurement of crystallographic parameters using scanning transmission electron microsco..

Atomic resolution imaging using electron energy-loss phonon spectroscopy

NR Lugg, BD Forbes, SD Findlay, LJ Allen

2015-04-20

Recent developments have improved the attainable energy resolution in electron energy-loss spectroscopy in aberration-corrected sc..

Modelling the inelastic scattering of fast electrons

LJ Allen, AJ D'Alfonso, SD Findlay

2015-04-01

Imaging at atomic resolution based on the inelastic scattering of electrons has become firmly established in the last three decade..

Local observation of the site occupancy of MN in a MnFePSi compound

MJ Neish, MP Oxley, J Guo, BC Sales, LJ Allen, MF Chisholm

2015-03-11

MnFePSi compounds are promising materials for magnetic refrigeration as they exhibit a giant magnetocaloric effect. From first pri..

Direct observation of depth-dependent atomic displacements associated with dislocations in gallium nitride

JG Lozano, H Yang, MP Guerrero-Lebrero, AJ D'Alfonso, A Yasuhara, E Okunishi, S Zhang, CJ Humphreys, LJ Allen, PL Galindo, PB Hirsch, PD Nellist

2014-09-24

We demonstrate that the aberration-corrected scanning transmission electron microscope has a sufficiently small depth of field to ..

Comment on “Electromagnetic Vortex Fields, Spin, and Spin-Orbit Interactions in Electron Vorticesâ€

P Schattschneider, JJ Rehr, LJ Allen

2014-07-07

A Comment on the Letter by S. Lloyd et al., Phys. Rev. Lett. 109, 254801 (2012).PRLTAO0031-900710.1103/PhysRevLett.109.254801 © 20..

Quantitative elemental mapping at atomic resolution using X-ray spectroscopy

G Kothleitner, MJ Neish, NR Lugg, SD Findlay, W Grogger, F Hofer, LJ Allen

2014-02-26

Elemental mapping using energy-dispersive x-ray spectroscopy in scanning transmission electron microscopy, a well-established tech..

Elemental mapping in achromatic atomic-resolution energy-filtered transmission electron microscopy

BD Forbes, L Houben, J Mayer, RE Dunin-Borkowski, LJ Allen

2014-01-01

We present atomic-resolution energy-filtered transmission electron microscopy (EFTEM) images obtained with the chromatic-aberratio..

Practical aspects of removing the effects of elastic and thermal diffuse scattering from spectroscopic data for single crystals

NR Lugg, MJ Neish, SD Findlay, LJ Allen

2014-01-01

A method to remove the effects of elastic and thermal diffuse scattering (TDS) of the incident electron probe from electron energy..

Three-dimensional imaging of individual dopant atoms in SrTiO3

J Hwang, JY Zhang, AJ D'Alfonso, LJ Allen, S Stemmer

2013-12-26

We report on three-dimensional (3D) imaging of individual Gd dopant atoms in a thin (∼2.3 nm) foil of SrTiO<inf>3</inf>, using qua..

Contrast in atomically resolved EF-SCEM imaging

P Wang, AJ D'Alfonso, A Hashimoto, AJ Morgan, M Takeguchi, K Mitsuishi, M Shimojo, AI Kirkland, LJ Allen, PD Nellist

2013-11-01

Energy-filtered scanning confocal electron microscopy (EF-SCEM) is a technique that uses the reduced depth of field of an aberrati..

The interaction of a nanoscale coherent helium-ion probe with a crystal

AJ D'Alfonso, BD Forbes, LJ Allen

2013-11-01

Thickness fringing was recently observed in helium ion microscopy (HIM) when imaging magnesium oxide cubes using a 40. keV converg..

Probe integrated scattering cross sections in the analysis of atomic resolution HAADF STEM images

H E, KE MacArthur, TJ Pennycook, E Okunishi, AJ D'Alfonso, NR Lugg, LJ Allen, PD Nellist

2013-10-01

The physical basis for using a probe-position integrated cross section (PICS) for a single column of atoms as an effective way to ..

Detecting the direction of oxygen bonding in SrTiO3

MJ Neish, NR Lugg, SD Findlay, M Haruta, K Kimoto, LJ Allen

2013-09-11

The near-edge fine structure of an ionization edge in electron energy-loss spectroscopy provides bonding and elemental information..

Atomic resolution chemical bond analysis of oxygen in La 2CuO4

M Haruta, T Nagai, NR Lugg, MJ Neish, M Nagao, K Kurashima, LJ Allen, T Mizoguchi, K Kimoto

2013-08-28

The distorted CuO<inf>6</inf> octahedron in La<inf>2</inf>CuO<inf>4</inf> was studied using aberration-corrected scanning transmis..

Achromatic elemental mapping beyond the nanoscale in the transmission electron microscope

KW Urban, J Mayer, JR Jinschek, MJ Neish, NR Lugg, LJ Allen

2013-05-02

Newly developed achromatic electron optics allows the use of wide energy windows and makes feasible energy-filtered transmission e..

Secondary electron imaging at atomic resolution using a focused coherent electron probe

HG Brown, AJ D'Alfonso, LJ Allen

2013-02-05

Atomic resolution imaging using secondary electrons (emitted as a result of the interaction of incident fast electrons with a spec..

Removing the effects of elastic and thermal scattering from electron energy-loss spectroscopic data

NR Lugg, M Haruta, MJ Neish, SD Findlay, T Mizoguchi, K Kimoto, LJ Allen

2012-10-29

Electron energy-loss spectroscopy (EELS) studies in scanning transmission electron microscopy are widely used to investigate the l..

Nanohalos: A manifestation of electron channelling in gold nanoparticles

G Ruben, P Wang, AJ D'Alfonso, PD Nellist, LJ Allen

2012-09-01

We discuss interesting haloing effects observed in experimental images of gold nanoparticles obtained using aberration-corrected s..

Contribution of thermally scattered electrons to atomic resolution elemental maps

BD Forbes, AJ D'Alfonso, REA Williams, R Srinivasan, HL Fraser, DW McComb, B Freitag, DO Klenov, LJ Allen

2012-07-18

Electron energy-loss spectroscopy (EELS) and energy dispersive x-ray (EDX) analysis in scanning transmission electron microscopy (..