Size selective investigations of spectral and emission properties of small particles and nanotubes [Elektronische Ressource] / Andriy Hloskovskyy (Andrei Gloskovskii)

Andrei Teleman

Sujets

• Physik

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2006
• Nombre de lectures: 17
• Langue: English
• Poids de l'ouvrage: 6 Mo

Extrait

Size-selective investigations of spectral and emission
properties of small particles and nanotubes








Dissertation zur Erlangung des Grades
„Doktor der Naturwissenschaften“
am Fachbereich für Physik der Johannes Gutenberg-Universität in Mainz





Diplom-Physiker Andriy Hloskovskyy (Andrei Gloskovskii)
geb. in Lwow (Ukraine)














Mainz, Juni 2006
Part of this work has been published in:


Electrical and emission properties of current-carrying silver cluster films detected by an
emission electron microscope
A. Gloskovskii, D. Valdaitsev, S.A. Nepijko, N.N. Sedov, G. Schönhense
Appl. Phys. A 79 (2004) 707–712


Electrical and emission properties of current-carrying silver nanocluster films investigated
by emission electron microscopy
A. Gloskovskii, D.A. Valdaitsev, S.A. Nepijko, G. Schönhense
Microsc. Microanal. 9, Suppl.3 (2003) 176–177


Time-of-Flight Photoelectron Spectromicroscopy of Single MoS nanotubes 2
A. Gloskovskii, S. A. Nepijko, M. Cinchetti, G. Schönhense, G. H. Fecher, H. C. Kandpal,
C. Felser, H. A. Therese, N. Zink, W. Tremel, A. Oelsner
J. Appl. Phys. (2006) accepted


Measurement of the electric field distribution and potentials on the object surface in an
emission electron microscope without restriction of the electron beams
S.A. Nepijko, A.Gloskovskii, N.N. Sedov, G. Schönhense
Journal of Microscopy 211 (2003) 89–94


Lateral resolving power of a time-of-flight photoemission electron microscope
S.A. Nepijko, A. Oelsner, A. Krasyuk, A. Gloskovskii, N.N. Sedov, C.M. Schneider,
G. Schönhense
Appl. Phys. A 78 (2004) 47–51

Emission electron microscopy of nanoparticles in strong fs laser fields
M. Cinchetti, A. Gloskovskii, D.A. Valdaitsev, A. Oelsner, G.H. Fecher, S.A. Nepijko,
H.J. Elmers, G. Schönhense
Microsc. Microanal. 9, Suppl.3 (2003) 168–169.


Photoemission time-of-flight spectromicroscopy of Ag nanoparticle films on Si(111)
M. Cinchetti, D.A. Valdaitsev, A. Gloskovskii, A. Oelsner, S.A. Nepijko, G. Schönhense
J. Electron. Spectr. Rel. Phenom. 137-140 (2004) 249–257


Articles in preparation:

Electron emission from nanoparticle Ag film excited by fs-laser radiation
A. Gloskovskii, D. A. Valdaitsev, S. A. Nepijko, J. Lange, M. Bauer, M. Aeschlimann,
G. Schönhense
In preparation


TEM and X-ray absorption study of Vanadium oxide nanotubes
A.Gloskovskii, S.A. Nepijko, G. Schönhense, H.A. Therese, A.Reiber, H.C. Kandpal,
G. H. Fecher, W. Tremel, M. Klimiankou
In preparation


Further related publications:

Element specific magnetic moments from core-absorption magnetic circular dichroism of
the doped Heusler alloy Co Cr Fe Al 2 0.6 0.4
H.J. Elmers, G.H. Fecher, D. Valdaitsev, S.A. Nepijko, A. Gloskovskii, G. Jakob,
G. Schönhense, S. Wurmehl, T. Block, C. Felser, P.-C. Hsu, W.-L. Tsai, S. Cramm
Phys. Rev. B 67 (2003) 104412 / 1–7
Investigation of a novel material for magnetoelectronics: Co Cr Fe Al 2 0.6 0.4
C. Felser, B. Heitkamp, F. Kronast, D. Schmitz, S. Cramm, H.A. Dürr, H.J. Elmers,
G.H. Fecher, S. Wurmehl, T. Block, D. Valdaitsev, S.A. Nepijko, A.Gloskovskii, G. Jakob,
G. Schönhense, W. Eberhardt
J. Phys.: Condens. Matter 15 (2003) 7019–7027


Photoemission Electron Microscopy as a tool for the investigation of optical near fields
M. Cinchetti, A. Gloskovskii, S.A. Nepijko, G. Schönhense, H. Rochholz, M. Kreiter
Phys. Rev. Lett. 95 (2005) 047601 / 1–4

Contents

Introduction .......................................................................................................3
Chapter 1. Theory .............................................................................................7
1.1 Thermal equations..............................................................................................................7
1.2 Mechanisms of electron emission from current-carrying thin metal cluster films ..........11
1.2.1 Field emission mechanism................................................................................12
1.2.2 Emission of hot electrons..................................................................................13
1.3 Mechanisms of electron emission under femtosecond laser excitation...........................15
1.3.1 Multiphoton photoemission (nPPE)..................................................................16
1.3.2 Thermionic emission.........................................................................................20
1.3.3 Thermally-assisted nPPE21
1.3.4 Optical field emission .......................................................................................24
1.4 Statistical approach to the light absorption by small metal particles...............................27
Chapter 2. Experimental details....................................................................32
2.1 UHV components ............................................................................................................32
2.2 General layout of the photoemission electron microscope (PEEM)................................33
2.2.1 PEEM in time-of-flight mode ...........................................................................33
2.2.2 PEEM with imaging energy filter .....................................................................35
2.3 Set-up for the observation of current-induced emission..................................................37
2.4 Laser systems...................................................................................................................37
Chapter 3. Results and discussion .................................................................40
3.1. Electrical and emission properties of current-carrying silver cluster films ....................40
3.1.1 Sample preparation ...........................................................................................40
3.1.2 Measurements of electron and photon emission versus applied voltage ..........41
3.1.3 Determination of the potential distribution in the film .....................................44
3.1.4 Formation of the field contrast in an emission electron microscope ................47
3.1.5 Investigation of the local electron emission......................................................49
3.1.6 Investigation of electron emission at low voltages ...........................................52
3.1.7 Discussion and conclusions ..............................................................................56
3.2 Emission properties of metal cluster films under femtosecond laser excitation..............58

3.2.1 Electron yield spectroscopy of Ag and Au nanoparticle films excited by
ultrashort fs-laser pulses.............................................................................................58
3.2.1.1 Sample preparation and characterization ...........................................58
3.2.1.2 Results ................................................................................................63
3.2.1.3 Discussion and conclusions................................................................71
3.2.2 Spectromicroscopy of Ag nanoparticle films....................................................78
3.2.2.1 Sa ...........................................78
3.2.2.2 Wavelength dependence of the images. .............................................80
3.2.2.3 Dependence on laser power85
3.2.2.4 Microspectroscopy of the emitted electrons.......................................87
3.3. Size-selective time-of-flight spectromicroscopy of MoS nanotubes.............................91 2
3.3.1 Sample preparation and characterization ..........................................................92
3.3.2 Results...............................................................................................................93
3.3.3 DOS calculations...............................................................................................94
3.3.4 Discussion and conclusions ..............................................................................95
Conclusions and outlook.................................................................................98
List of used abbreviations.............................................................................104
Bibliography ..................................................................................................105

Introduction 3
Introduction

Metallic thin films structured by various techniques in the field of
nanotechnology play a crucial role in high-tech research and development. E.g.,
the microelectronics industry strongly needs the understanding of the
electrophysical properties of thin films and small structures in order to fabricate
integrated circuits with critical dimensions of 100 nm or even smaller. Electron
emission studies from such nanostructures are a valuable tool for the study of their