Searched for: faculty:"Applied%5C%2BSciences"
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Aerts, M. (author)
Thesis about the charge carrier dynamics in PbSe and PbS semiconductor nanocrystals. The main goal of the research is to assess their potential as new materials for high-efficiency solar cells. The nanocrystals under investigation consist of PbSe quantum dots (Ch 2), PbSe nanorods (Ch 3 & 4) and PbS nanosheets (Ch 6), and the spectroscopic...
doctoral thesis 2015
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Broeken, J. (author), Rieger, B. (author), Stallinga, S. (author)
We propose a method for simultaneously measuring the position and emission color of single fluorescent emitters based on the use of a large pitch diffraction grating in the emission light path. The grating produces satellite spots adjacent to the main spot; the relative distance between the spots is a measure for the emission wavelength. We...
journal article 2014
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Jansen, K. (author), Wu, M. (author), Van der Steen, A.F.W. (author), Van Soest, G. (author)
Spectroscopic intravascular photoacoustic imaging (sIVPA) has shown promise to detect and distinguish lipids in atherosclerotic plaques. sIVPA generally utilizes one of the two high absorption bands in the lipid absorption spectrum at 1.2 ?m and 1.7 ?m. Specific absorption signatures of various lipid compounds within the bands in either...
journal article 2014
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Jansen, K. (author), Van der Steen, A.F.W. (author), Wu, M. (author), Van Beusekom, H.M.M. (author), Springeling, G. (author), Li, X. (author), Zhou, Q. (author), Shung, K.K. (author), De Kleijn, D.P.V. (author), Van Soest, G. (author)
The natural history of atherosclerosis is marked by changes in the lipid biochemistry in the diseased arterial wall. As lesions become more vulnerable, different cholesterol species accumulate in the plaque. Understanding unstable atherosclerosis as a pharmacological and interventional therapeutic target requires chemically specific imaging of...
journal article 2014
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Khodyuk, I.V. (author)
A scintillator is a transparent material that emits a flash of light when it absorbs a ?-ray photon or an energetic particle. Scintillation crystals are widely used as spectroscopic detectors of ionizing radiation in nuclear science, space exploration, medical imaging, homeland security, etc. This thesis is about nonproportional response of...
doctoral thesis 2013
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Ramakrishnan, G. (author), Kumar, N. (author), Planken, P.C.M. (author), Tanaka, D. (author), Kajikawa, K. (author)
Emission of terahertz radiation is observed when surface plasmons are excited on a thin film of gold, in the Kretschmann geometry. When a hemicyanine-terminated alkanethiol self-assembled monolayer of thickness 1.2 nm is deposited on the gold film, stronger terahertz emission is observed. Our experimental results confirm that enhanced terahertz...
journal article 2012
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Zeitouny, M.G. (author)
In the recent years, precision measurement techniques in the field of optical science have improved with the advances in the phase stabilization of femtosecond lasers. Due to their unique properties, phase stabilized femtosecond lasers, also known as frequency comb lasers, are used as a versatile tools, not only for time and frequency metrology,...
doctoral thesis 2011
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Ramakrishnan, G. (author), Planken, P.C.M. (author)
Emission of pulses of electromagnetic radiation in the terahertz range is observed when ultrathin gold films on glass are illuminated with femtosecond near-IR laser pulses. A distinct maximum is observed in the emitted terahertz amplitude from films of average thickness just above the percolation threshold. Our measurements suggest that the...
journal article 2011
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Almeida, A.R. (author)
Chemical processes are generally operated at elevated temperatures and pressures, and energy intensive separations are usually necessary. This thesis focuses on the production of cyclohexanone, which is an intermediate of high commercial importance as a result of its use in nylon-6 and nylon-6,6 production. Using TiO2 based photo-catalysis is a...
doctoral thesis 2010
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Chakkittakandy, R. (author)
Everyday we see around us many materials that are different from one another. We identify them on the basis of their shape, texture, smell, taste, color, etc with the help of our senses. Many times it is almost impossible to identify materials only with our senses. Then, one has to look into more fundamental aspects of the materials such as...
doctoral thesis 2010
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Ramakrishnan, G. (author), Chakkittakandy, R. (author), Planken, P.C.M. (author)
Generation of subpicosecond terahertz pulses is observed when graphite surfaces are illuminated with femtosecond near-infrared laser pulses. The nonlinear optical generation of THz pulses from graphite is unexpected since, in principle, the material possesses a centre of inversion symmetry. Experiments with highly oriented pyrolytic graphite...
journal article 2009
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Adam, A.J.L. (author), Planken, P.C.M. (author), Meloni, S. (author), Dik, J. (author)
We show terahertz reflection images of hidden paint layers in a painting on canvas and compare the results with X-ray Radiography and Infrared Reflectography. Our terahertz measurements show strong reflections from both the canvas/paint interface and from the raw umber/lead white interface, indicating sufficient refractive-index contrast. Our...
journal article 2009
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Adam, A.J.L. (author), Brok, J.M. (author), Seo, M.A. (author), Ahn, K.J. (author), Kim, D.S. (author), Kang, J.H. (author), Park, Q.H. (author), Nagel, M. (author), Planken, P.C.M. (author)
An erratum is presented to correct an error in the discussion section of [Opt. Express. 16, 7407-7417 (2008)] and to add a relevant reference on earlier work.
journal article 2008
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Chakkittakandy, R. (author), Corver, J.A.W.M. (author), Planken, P.C.M. (author)
We describe a simple terahertz (THz) time domain spectrometer with a bandwidth extending up to 7.5 THz. We show that by keeping the generation and detection crystals close to each other a high signal-to-noise ratio (SNR) can be achieved without using lock-in detection and dry nitrogen flushing. The observed spectra show very good agreement with...
journal article 2008
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Adam, A.J.L. (author), Brok, J.M. (author), Seo, M.A. (author), Ahn, K.J. (author), Kim, D.S. (author), Kang, J.H. (author), Park, Q.H. (author), Nagel, M. (author), Planken, P.C.M. (author)
Using terahertz-light excitation, we have measured with sub-wavelength spatial, and sub-cycle temporal resolution the time- and frequency-dependent electric-field and surface-charge density in the vicinity of small metallic holes. In addition to a singularity like concentration of the electric field near the hole edges, we observe, that holes...
journal article 2008
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Hajenius, M. (author)
Heterodyne measurements in the frequency range between 1 - 6 terahertz (THz) are expected to provide a wealth of information on questions ranging from the formation of new stars and the conditions under which life formed on our own planet to the ozone hole in our own atmosphere. Hot electron bolometers (HEB) are currently the only suitable...
doctoral thesis 2007
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Lee, J.W. (author), Seo, M.A. (author), Park, D.J. (author), Kim, D.S. (author), Jeoung, S.C. (author), Lienau, C. (author), Park, Q.H. (author), Planken, P.C.M. (author)
Terahertz transmission filters have been manufactured by perforating metal films with various geometric shapes using femtosecond laser machining. Two dimensional arrays of square, circular, rectangular, cshaped, and epsilon-shaped holes all support over 99% transmission at specific frequencies determined by geometric shape, symmetry,...
journal article 2006
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Van Veen, E.H. (author), Roekaerts, D. (author)
An optimal system for temperature measurements by coherent anti-Stokes Raman spectroscopy (CARS) in turbulent flames and flows is presented. In addition to a single-mode pump laser and a modeless dye laser, an echelle spectrometer with a cross disperser is used. This system permits simultaneous measurement of the N2 CARS spectrum and the...
journal article 2005
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Van der Valk, N.C.J. (author), Planken, P.C.M. (author), Buijserd, A.N. (author), Bakker, H.J. (author)
We present measurements on terahertz generation by optical rectification, in which both the thickness of the generation crystal and the wavelength of the generating optical pulse are varied. The difference between the group velocity at optical frequencies and the phase velocity at terahertz frequencies affects the time trace and spectrum of the...
journal article 2005
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Moolenaar, A.A. (author)
doctoral thesis 1994
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