The signal-to-noise ratio of measurements by electron holography could be considerably improved if longer exposure times were possible: increasing the number of electrons contributing to the hologram improves the counting statistics. However, instrumental instabilities causing drift in the hologram fringes and specimen position make acquisition times of above a few seconds counterproductive. The current approach is to acquire image stacks of holograms, with short exposure times, followed by numerical realignment through sophisticated post-processing. The associated data storage and manipulation make in-situ and tomography experiments extremely cumbersome. Here, we implement dynamic automation of electron holography experiments to overcome these problems. The real-time drift measurement and feedback control of the instrument allow single holograms to be acquired with exposure times of 30 min or more. Indeed, there are no longer any limitations from instrumental instabilities and only those imposed by the specimen itself. Furthermore, automation allows the implementation of sophisticated phase reconstruction techniques based on precise control of the experimental conditions. Smart acquisition of electron holograms preludes future computer-controlled electron microscopy capabilities.
References
1.
S. J.
Erasmus
and K. C. A.
Smith
, “An automatic focusing and astigmatism correction system for the SEM and CTEM
,” J. Microscopy (Oxford)
127
, 185
–199
(1982
).2.
W. O.
Saxton
, D. J.
Smith
, and S. J.
Erasmus
, “Procedures for focusing, stigmating and alignment in high resolution electron microscopy
,” J. Microscopy (Oxford)
130
, 187
–201
(1983
).3.
A. J.
Koster
, A.
Van Den Bos
, and K. D.
Van Der Mast
, “An autofocus method for a TEM
,” Ultramicroscopy
21
, 209
–222
(1987
).4.
S.
Uhlemann
and M.
Haider
, “Residual wave aberrations in the first spherical aberration corrected transmission electron microscope
,” Ultramicroscopy
72
, 109
–119
(1998
).5.
K.
Dierksen
, D.
Typke
, R.
Hegerl
, A. J.
Koster
, and W.
Baumeister
, “Towards automatic electron tomography
,” Ultramicroscopy
40
, 71
–87
(1992
).6.
U.
Kolb
, T.
Gorelik
, C.
Ku
, M. T.
Otten
, and D.
Hubert
, “Towards automated diffraction tomography: Part I—Data acquisition
,” Ultramicroscopy
107
, 507
–513
(2007
).7.
D.
Wolf
, A.
Lubk
, H.
Lichte
, and H.
Friedrich
, “Towards automated electron holographic tomography for 3D mapping of electrostatic potentials
,” Ultramicroscopy
110
, 390
–399
(2010
).8.
A.
Korinek
, F.
Beck
, W.
Baumeister
, S.
Nickell
, and J. M.
Plitzko
, “Computer controlled cryo-electron microscopy—TOM2 a software package for high-throughput applications
,” J. Struct. Biol.
175
, 394
–405
(2011
).9.
Y. Z.
Tan
, A.
Cheng
, C. S.
Potter
, and B.
Carragher
, “Automated data collection in single particle electron microscopy
,” Microscopy
65
, 43
–56
(2016
).10.
A. J.
Koster
, H.
Chen
, J. W.
Sedat
, and D. A.
Agard
, “Automated microscopy for electron tomography
,” Ultramicroscopy
46
, 207
–227
(1992
).11.
A.
Tejada
, A. J.
den Dekker
, and W.
Van den Broek
, “Introducing measure-by-wire, the systematic use of systems and control theory in transmission electron microscopy
,” Ultramicroscopy
111
, 1581
–1591
(2011
).12.
A.
Tejada
, W.
Van den Broek
, and A. J.
den Dekker
, “Measure-by-wire (MBW): An automatic control framework for high-throughput transmission electron microscopy
,” Adv. Imaging Electron Phys.
179
, 291
–345
(2013
).13.
V. V.
Volkov
, M. G.
Han
, and Y.
Zhu
, “Double resolution electron holography with simple Fourier transform of fringe-shifted holograms
,” Ultramicroscopy
134
, 175
–184
(2013
).14.
Q.
Ru
, J.
Endo
, T.
Tanji
, and A.
Tonomura
, “Phase-shifting electron holography by beam tilting
,” Appl. Phys. Lett.
59
, 2372
–2374
(1991
).15.
M. R.
McCartney
, D. J.
Smith
, R.
Hull
, J. C.
Bean
, E.
Voelkl
, and B.
Frost
, “Direct observation of potential distribution across Si/Si p-n junctions using off-axis electron holography
,” Appl. Phys. Lett.
65
, 2603
–2605
(1994
).16.
W. D.
Rau
, P.
Schwander
, F. H.
Baumann
, W.
Höppner
, and A.
Ourmazd
, “Two-dimensional mapping of the electrostatic potential in transistors by electron holography
,” Phys. Rev. Lett.
82
, 2614
–2617
(1999
).17.
R. E.
Dunin-Borkowski
, M. R.
McCartney
, D. J.
Smith
, and S. S. P.
Parkin
, “Towards quantitative electron holography of magnetic thin films using in situ magnetization reversal
,” Ultramicroscopy
74
, 61
–73
(1998
).18.
M. J.
Hÿtch
, F.
Houdellier
, F.
Hüe
, and E.
Snoeck
, “Nanoscale holographic interferometry for strain measurements in electronic devices
,” Nature
453
, 1086
–1089
(2008
).19.
H.
Lichte
, K.-H.
Herrmann
, and F.
Lenz
, “Electron noise in off-axis image plane holography
,” Optik
77
, 135
–140
(1987
).20.
W. J.
de Ruijter
and J. K.
Weiss
, “Detection limits in quantitative off-axis electron holography
,” Ultramicroscopy
50
, 269
–283
(1993
).21.
M.
Lehmann
and H.
Lichte
, “Electron holographic material analysis at atomic dimensions
,” Cryst. Res. Technol.
40
, 149
–160
(2005
).22.
D.
Cooper
, R.
Truche
, P.
Rivallin
, J.-M.
Hartmann
, F.
Laugier
, F.
Bertin
, A.
Chabli
, and J.-L.
Rouvière
, “Medium resolution off-axis electron holography with millivolt sensitivity
,” Appl. Phys. Lett.
91
, 143501
(2007
).23.
E.
Voelkl
and D.
Tang
, “Approaching routine 2π/1000 phase resolution for off-axis type holography
,” Ultramicroscopy
110
, 447
–459
(2010
).24.
R. A.
McLeod
, M.
Bergen
, and M.
Malac
, “Phase measurement error in summation of electron holography series
,” Ultramicroscopy
141
, 38
–
50
(2014
).25.
T.
Niermann
and M.
Lehmann
, “Averaging scheme for atomic resolution off-axis electron holograms
,” Micron
63
, 28
–34
(2014
).26.
C.
Gatel
, X.
Fu
, V.
Serin
, M.
Eddrief
, V.
Etgens
, and B.
Warot-Fonrose
, “In depth spatially inhomogeneous phase transition in epitaxial MnAs film on GaAs(001)
,” Nano Lett.
17
, 2460
–2466
(2017
).27.
C.
Gatel
, B.
Warot-Fonrose
, N.
Bizière
, L. A.
Rodriguez
, D.
Reyes
, R.
Cours
, M.
Castiella
, and M.-J.
Casanove
, “Inhomogeneous spatial distribution of the magnetic transition in an iron-rhodium thin film
,” Nat. Commun.
8
, 15703
(2017
).28.
F.
Zheng
, F. N.
Rybakov
, A. B.
Borisov
, D.
Song
, S.
Wang
, Z.-A.
Li
, H.
Du
, N. S.
Kiselev
, J.
Caron
, A.
Kovacs
, M.
Tian
, Y.
Zhang
, S.
Blügel
, and R. E.
Dunin-Borkowski
, “Experimental observation of chiral magnetic bobbers in B20-type FeGe
,” Nat. Nanotechnol.
13
, 451
–455
(2018
).29.
T.
Tanigaki
, Y.
Takahashi
, T.
Shimakura
, T.
Akashi
, R.
Tsuneta
, A.
Sugawara
, and D.
Shindo
, “Three-dimensional observations of magnetic vortex cores in stacked ferromagnetic discs
,” Nano Lett.
15
, 1309
–1314
(2015
).30.
J.
Liu
, H.
Li
, L.
Zhang
, M.
Rames
, M.
Zhang
, Y.
Yu
, B.
Peng
, C. D.
Celis
, A.
Xu
, Q.
Zou
, X.
Yang
, X.
Chen
, and G.
Ren
, “Fully mechanically controlled automated electron microscopic tomography
,” Sci. Rep.
6
, 29231
(2016
).31.
V.
Boureau
, R.
McLeod
, B.
Mayall
, and D.
Cooper
, “Off-axis electron holography combining summation of hologram series with double-exposure phase-shifting: theory and application
,” Ultramicroscopy
193
, 52
–63
(2018
).32.
S. F.
Fu
, J. W.
Chen
, Z. J.
Wang
, and H. Q.
Cao
, “Experimental investigation of electron interference and electron holography
,” Optik
76
, 45
–47
(1987
).33.
G.
Matteucci
, G. F.
Missiroli
, J. W.
Chen
, and G.
Pozzi
, “Mapping microelectric and magnetic-fields with double-exposure electron holography
,” Appl. Phys. Lett.
52
, 176
–178
(1988
).34.
C.
Gatel
, F.
Houdellier
, and E.
Snoeck
, “Dynamical holographic Moires in a TEM
,” J. Phys. D: Appl. Phys.
49
, 324001
(2016
).35.
E.
Snoeck
, F.
Houdellier
, Y.
Taniguchi
, A.
Masseboeuf
, C.
Gatel
, J.
Nicolai
, and M. J.
Hÿtch
, “Off-axial aberration correction using a B-COR for Lorentz and HREM modes
,” Microsc. Microanal.
20
(S3
), 932
–933
(2014
).36.
K.
Harada
, A.
Tonomura
, Y.
Togawa
, T.
Akashi
, and T.
Matsuda
, “Double-biprism electron interferometry
,” Appl. Phys. Lett.
84
, 3229
–3231
(2004
).37.
See http://www.hremresearch.com for A commercial version of HoloLive, a plug-in for DigitalMicrograph (Gatan) for real-time hologram phase visualisation, was developed in collaboration with HREM Research Inc.
38.
F.
Houdellier
, G. M.
Caruso
, S.
Weber
, M.
Kociak
, and A.
Arbouet
, “Development of a high brightness ultrafast transmission electron microscope based on a laser-driven cold field emission source
,” Ultramicroscopy
186
, 128
–138
(2018
).© 2018 Author(s).
2018
Author(s)
You do not currently have access to this content.
