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FUNMAT research
activities in
Nanotechnology
Contents • Short description of research
fields
• Relevant publications
Short description of research fields
Nanoscience is well established as an area of experimental and theoretical
studies of nanometer-size materials and devices. The heart of thes new area is
mesoscopic physics. By now mesoscopic physics in Norway is presented by
theoretical activity, however, new experimental activities are now to be
initialized. New clean rooms (1000 m2) become available at the Norwegian
Microtechnology Center (NMC-MRL) in 2002 for fundamental (UiO) and applied
research (SINTEF). Here, the involved university research activities comprise
physical electronics and materials chemistry. In addition, targeted research
towards synthesis, characterization and modeling of nanoparticles is here
counted as nanoscience, whereas activities relating to catalysis, surface
science and biomaterials are described under different headings in the FUNMAT
overview for the 6FP.
Mesoscopic physics: Theory The research topics in focus
are:
Two-dimensional structures - Non-stationary effects in
two dimensional electron gas (2DEG), response to ac perturbations and surface
acoustic waves, properties of 2DEG structures under conditions of the quantum
Hall effect.
Quantum channels and quantum point contacts -
quantized electron drag through quasi one dimensional (1D)structures by surface
acoustic waves, noise properties between quantum point contacts between normal
metals and superconductors, fundamental aspects of transport through quasi-1D
structures including normal conductors and superconductors.
Granular materials, Nano-powders - electromagnetic and acoustic
response (both linear and nonlinear).
Quantum dots and rings
-single-electron devices, non-equilibrium effects in magnetization and
electromagnetic response.
Hybrid structures involving
superconductors -dynamics and noise properties.
Nano-mechanics in normal and superconductor structures - "shuttling"
of electrons by mechanical motion in nanostructures, coherent transfer of
Cooper pairs between superconductors by movable grains.
Coherent
electron electron transport through nanostructures directed to quantum
computation.
Mesoscopic effects in vortex matter in
superconductors - studies of motion of vortices in superconductors in
small systems having size of intrinsic scales in vortex matter.
The above activities take place in a close collaboration with many
organizations, and have resulted in many publications, for a selection, see
Relevant publications.
Physical electronics: Experiment The research topics of main
interest are:
Nanoclusters of germanium in silicon dioxide
films – synthesis and studies of structural, electrical and optical
properties.
Quantum structures in silicon carbide and gallium
nitride – correlation of electrical properties with crystalline
structure and optical performance.
Low dimensional structures in
SiGe and SiGeC – effect of internal strain on electrical and optical
performance and atomic diffusivity.
Molecular- and
nanoelectronics – electron transport through macromolecules (carbon
nanotubes, DNA), the effect of electric field and optical excitation.
Some of these activities are carried out in close collaboration
with European partners and have resulted in several common publications.
Materials chemistry Activities in sol-gel technology,
catalysis, thin film growths etc., are all relevant for growth of
nanoscale/nanostructured materials. In addition to interests in
characterisation of properties of nanostructured materials, as well as dense
and porous (nano)materials, novel interests of the FUNMAT partners are:
Synthesis: Development of original routes to inorganic products;
Combination of organic and inorganic building blocks on a molecular level
(molecular or 1D-, 2D-, 3D-hybride materials); Ability to monitor
supramolecular units in solutions for subsequent building of materials
Layered or one-dimensional nanostructures, the latter e.g. via
chemical means by utilizing micro/mesoporous precursors. Layered materials
include crystalline hydroxides, oxides (silicates and derivatives), as well as
artificial materials made by CVD-methods. These include superlattices of
complex oxides, other functional inorganic compounds, and hybrid
organic-inorganic layered materials.
Materials with natural
nanodimensions; molecular materials; nanotubes of different types of
inorganic materials
Sol-gel technology and precipitation
reactions for nanoparticle formation, including development of suitable
single-source precursors
Thermodynamic considerations of
stability of nanoparticles
Selection of relevant publications
Mesoscopic physics: Theory • "Coherent transfer of
Cooper pairs by a movable grain", L. Y. Gorelik, A. Isacsson, Y. M. Galperin,
R. I. Shekhter, M. Jonson, Nature 411, 454 (2001).
• "Kondo
Temperature for the Two-Channel Kondo Models of Tunneling Centers ", I. L.
Aleiner, B. L. Altshuler, Y. M. Galperin, Phys. Rev. Lett. 86, 2629 (2000)
• “Giant Nonlinear Absorption by an Ensemble of Metallic
Grains” Y. M. Galperin, K. A. Chao Foundations of Physics 30, 2135-2150
(2000)
• "High-frequency hopping conductivity in the quantum
Hall effect regime: Acoustical studies", I. L. Drichko, A. M. Diakonov, I. Yu.
Smirnov, Y. M. Galperin, and A. I. Toropov, Phys. Rev. B 62, 7470 (2000).
• "Nonlinear absorption of surface acoustic waves by composite
fermions", Joakim Bergli, Yuri Galperin, Europhys. Lett.54 (5), 661-667 (2001).
• Impurity-induced dephasing of Andreev states,
N. I.
Lundin and Y. M. Galperin, Phys. Rev. 63 (9), Article 094505 (2001)
Physical electronics. Experiment •
“Vacancy-Related Deep Levels in N-Type Si1-xGex Strained Layers” E.V.
Monakhov, A.Yu. Kuznetsov and B.G. Svensson, Phys. Rev. B 63, 245322
(2001).
• “Comparative Study of Divacancy and E-Center
Electronic Levels in Si and Strained Si0.87Ge0.13 Layers”, E.V. Monakhov,
A.Yu. Kuznetsov and B.G. Svensson, J. Appl. Phys. 87, 4629 (2000).
• “Thermal Donor and Antimony Energy Levels in Relaxed Si1-xGex
Layers” E.V. Monakhov, A.Yu. Kuznetsov, B.G. Svensson, and A.
Nylandsted-Larsen, Phys. Rev. B 61, 1708 (2000).
Materials chemistry • M.-A. Einarsrud, M.B. Kirkedelen,
E. Nilsen, K. Mortensen, and J. Samseth, Structural Development of Silica Gels
Aged in TEOS, J. Non-Cryst. Solids, 231 (1998) 10-16.
• S.
Hæreid, J. Anderson, M.-A. Einarsrud, D.W. Hua, and D.M. Smith, Thermal
and Temporal Aging of TMOS Based Aerogel Precursors in Water, J. Non-Cryst.
Solids, 185 (1995) 221-226.
• C. Simon, R. Bredesen and C.
Denonville, “Characterization of Surface Modified Alumina Membranes”,
in Proc. ICIM’98, pp.416-19 (1998).
• M. Veith, A. Altherr,
N. Lecerf, S. Mathur, K. Valtchev, E. Fritscher, “Molecular Precursor
Approach to Nano-scaled Ceramics and Metal/Metal Oxide Composites”,
NanoStructured Materials, Vol. 12, 191-194, (1999).
• C. Simon,
B. Holme, C. Prevost and R. Bredesen, “In-situ characterisation of the
Formation of nanoparticle-based coatings”, presented at Sol-Gel 2001,
Padova, 16-21. September 2001 (2001).
• S. Mathur, H. Shen, N.
Lecerf, A. Kjekshus, H. Fjellvåg, G. F. Goya, “Nanocrystalline
Orthoferrite GdFeO3 from a Novel Heterobimetallic Precursor”, Advanced
Materials, submittted for publication (2002).
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