Bose-Einstein condensates of sodium atoms have been confined in an optical dipole trap using a single focused infrared laser beam. This eliminates the restrictions of magnetic traps for further studies of atom lasers and Bose-Einstein condensates. More than 5 3 106 condensed atoms were transferred into the optical trap. Densities of up to 3 3 1015 cm23 of Bose condensed atoms were obtained, all...

This paper presents results of experiments using a variety of antennas inside several buildings. Path loss models are presented for the 1.3 GHz and 4.0 GHz bands, and indicate little difference in indoor path loss throughout the low-microwave region. Results show that line-of-sight (LOS) channels offer significantly more cross-polarization discrimination than obstructed (OBS) channels. A profou...

A detailed description of the conformational plasticity of double stranded DNA (ds) is a necessary framework for understanding protein-DNA interactions. Until now, however structure and kinetics of the transition from the basic conformation of ds-DNA (B state) to the 1.7 times longer and partially unwound conformation (S state) have not been defined. The force-extension relation of the ds-DNA o...

The Monte Carlo technique with angle biasing is used to simulate the optical coherence tomography (OCT) signal from homogeneous turbid media. The OCT signal is divided into two categories: one is from a target imaging layer in the medium (Class I); the other is from the rest of the medium (Class II). These two classes of signal are very different in their spatial distributions, angular distribu...

A 40-km length of optical f iber whose group-velocity dispersion decreases exponentially along its length has been fabricated. We experimentally compare the propagation of picosecond solitons through the dispersiondecreasing fiber with that through a constant-dispersion fiber of the same path-averaged dispersion. For a wide range of input powers, the output pulse widths of the dispersion-decrea...

Optical waveguide is the fundamental element that interconnects the various devices of an optical integrated circuit. In this paper, the propagation characteristics of ridge and buried waveguides have been investigated on light intensity distribution within the structure. The analysis has been done by varying the thickness and also the width of both ridge and buried optical waveguide. The norma...

We interpret the well known fact that the equations for light rays in the Kottler or Schwarzschild-de Sitter metric are independent of the cosmological constant in terms of the projective equivalence of the optical metric for any value of Λ. We explain why this does not imply that lensing phenomena are independent of Λ. Motivated by this example, we find a large collection of one-parameter fami...

Carbon nanotubes show vast potential to be used as building blocks for photodetection applications. However, measurements of fundamental optical properties, such as the absorption coefficient and the dielectric constant, have not been accurately performed on a single pristine carbon nanotube. Here we show polarization-dependent photocurrent spectroscopy, performed on a p-n junction in a single ...

Solar energy is not only sustainable but also a clean alternative to be used as source of high temperature heat for many processes and power generation. However, the major drawback of solar energy is its transient nature. Especially in solar thermochemical processing, it is crucial to maintain constant or semiconstant temperatures inside the solar reactor. In our laboratory, we have developed a...