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Ann Phys 2020 Apr 24;532(4). Epub 2020 Feb 24.

Department of Optics and Optical Engineering, Institute of Photonics, University of Science and Technology of China, Hefei, Anhui 230026, China.

Near-field optical trapping can be realized with focused evanescent waves that are excited at the water-glass interface due to the total internal reflection, or with focused plasmonic waves excited on the water-gold interface. Herein, the performance of these two kinds of near-field optical trapping techniques is compared using the same optical microscope configuration. Experimental results show that only a single-micron polystyrene bead can be trapped by the focused evanescent waves, whereas many beads are simultaneously attracted to the center of the excited region by focused plasmonic waves. Read More

Ann Phys 2017 May 23;529(5). Epub 2017 Mar 23.

Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.

The properties of materials largely reflect the degree and character of the localization of the molecules comprising them so that the study and characterization of particle localization has central significance in both fundamental science and material design. Soft materials are often comprised of deformable molecules and many of their unique properties derive from the distinct nature of particle localization. We study localization in a model material composed of soft particles, hard nanoparticles with grafted layers of polymers, where the molecular characteristics of the grafted layers allow us to "tune" the softness of their interactions. Read More

Ann Phys 2016 04 7;528(3-4):295-306. Epub 2015 Dec 7.

Institute of Applied Physics Johannes Kepler University Linz Altenbergerstraße 69 4040 Linz Austria.

It is known (yet often ignored) from quantum mechanical or energetic considerations, that the threshold gain of the quasi-static spaser depends only on the dielectric functions of the metal and the gain material. Here, we derive this result from the purely classical electromagnetic scattering framework. This is of great importance, because electrodynamic modelling is far simpler than quantum mechanical one. Read More

Ann Phys 2016 Jan 7;528(1-2):102-107. Epub 2015 Dec 7.

University of Oxford Denys Wilkinson Building, Keble Road Oxford OX1 3RH UK.

The current status of flavour physics and the prospects for present and future experiments will be reviewed. Measurements in -physics, in which sensitive probes of new physics are the CKM angle γ, the Bs mixing phase ϕs, and the branching ratios of the rare decays B(s)0→μ+μ- , will be highlighted. Topics in charm and kaon physics, in which the measurements of ACP and the branching ratios of the rare decays K→πνν¯ are key measurements, will be discussed. Read More

Ann Phys 2015 Apr 16;527(3-4):296-310. Epub 2015 Mar 16.

King Abdullah Institute for Nanotechnology, King Saud University P.O. Box 2455, Riyadh, 11451, Saudi Arabia.

Thermodynamic properties of the one-dimensional (1D) quantum well (QW) with miscellaneous permutations of the Dirichlet (D) and Neumann (N) boundary conditions (BCs) at its edges in the perpendicular to the surfaces electric field [Formula: see text] are calculated. For the canonical ensemble, analytical expressions involving theta functions are found for the mean energy and heat capacity [Formula: see text] for the box with no applied voltage. Pronounced maximum accompanied by the adjacent minimum of the specific heat dependence on the temperature for the pure Neumann QW and their absence for other BCs are predicted and explained by the structure of the corresponding energy spectrum. Read More

Ann Phys 2015 Apr 18;527(3-4):278-295. Epub 2015 Mar 18.

King Abdullah Institute for Nanotechnology, King Saud University P.O. Box 2455, Riyadh, 11451, Saudi Arabia.

Analytical solutions of the Schrödinger equation for the one-dimensional quantum well with all possible permutations of the Dirichlet and Neumann boundary conditions (BCs) in perpendicular to the interfaces uniform electric field [Formula: see text] are used for the comparative investigation of their interaction and its influence on the properties of the system. Limiting cases of the weak and strong voltages allow an easy mathematical treatment and its clear physical explanation; in particular, for the small [Formula: see text], the perturbation theory derives for all geometries a linear dependence of the polarization on the field with the BC-dependent proportionality coefficient being positive (negative) for the ground (excited) states. Simple two-level approximation elementary explains the negative polarizations as a result of the field-induced destructive interference of the unperturbed modes and shows that in this case the admixture of only the neighboring states plays a dominant role. Read More

Ann Phys 2012 Nov;524(11):687-696

Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA.

We present a new plasmonic device architecture based on ultrasmooth metallic surfaces with buried plasmonic nanostructures. Using template-stripping techniques, ultrathin gold films with less than 5 Å surface roughness are optically coupled to an arbitrary arrangement of buried metallic gratings, rings, and nanodots. As a prototypical example, we present linear plasmonic gratings buried under an ultrasmooth 20 nm thick gold surface for biosensing. Read More

Ann Phys 2012 Nov;524(11):741-750

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251 USA.

This study demonstrates the proof-of-principle of rapid surface modification of plasmonic nanostructured materials with oligonucleotides using low power microwave heating. Due to their interesting optical and electronic properties, silver nanoparticle films (SNFs, 2 nm thick) deposited onto glass slides were used as the model plasmonic nanostructured materials. Rapid surface modification of SNFs with oligonucleotides was carried out using two strategies (1) Strategy 1: for ss-oligonucleotides, surface hybridization and (2) Strategy 2: for ds-oligonucleotides, solution hybridization), where the samples were exposed to 10, 15, 30 and 60 seconds microwave heating. Read More

Ann Phys 2011 Nov 20;523(11):951-956. Epub 2011 Sep 20.

Institut für Physik TU Dortmund, 44221 Dortmund, Germany.

In my reply I present a re-analysis of the data of the Smithsonian Astrophysical Observatory (SAO). For this, a new data reduction method is introduced, allowing a drastic lowering of data scatter, so that the time series of the reduced data clearly shows the ≈ 1% variation of the terrestric solar irradiance in parallel with solar activity. The implications are discussed. Read More

Ann Phys 2011 Nov 20;523(11):946-950. Epub 2011 Sep 20.

Earth System Analysis, Potsdam Institute for Climate Impact Research (PIK) P.O. Box 60 12 03, 14412 Potsdam, Germany.

An analysis of ground-based observations of solar irradiance was recently published in this journal, reporting an apparent increase of solar irradiance on the ground of the order of 1% between solar minima and maxima [1]. Since the corresponding variations in total solar irradiance on top of the atmosphere are accurately determined from satellite observations to be of the order of 0.1% only [2], the one order of magnitude stronger effect in the terrestrial insolation data was interpreted as evidence for cosmic-ray induced aerosol formation in the atmosphere. Read More

Ann Phys 1948 ;2(5-6):270-2

Ann Phys 1948 ;2(5-6):242-55

Ann Phys 1947 Apr-May;6(4-5):251-60

Ann Phys 1947 Apr-May;6(4-5):241-50

Ann Phys 1947 Apr-May;6(4-5):229-40

Ann Phys 1947 Apr-May;6(4-5):219-28

Ann Phys 1947 Apr-May;6(4-5):207-18

Ann Phys 1947 Apr-May;6(4-5):169-80

Ann Phys 1947 Apr-May;6(4-5):153-68