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A holey fiber having a core with an elliptical-hole lattice structure, which is referred to as an elliptical-hole core circular-hole holey fiber (EC-CHF), can be easily designed as a single-polarization fiber by using the fundamental space-filling modes of the core and cladding lattices. However, because the guided mode in an EC-CHF has a polarization that arises from the large geometric anisotropy of the core lattice, the influence of the bending direction on the bending loss is a crucial issue for the practical implementation of EC-CHFs. Here, the bending losses of an EC-CHF bent in arbitrary angular orientations with respect to the core cross section are calculated numerically using the equivalent anisotropic step-index circular fiber model for a real EC-CHF, and the influence of the bending direction of the fiber on the bending loss is discussed. OCIS codes: 060.2310, 060.2400, 060.2420.

A short linear cavity erbium fiber laser is adapted to become a Q-switched laser by using a new and simple loss switching technique. The technique utilizes the inherent flexibility of optical fiber to rapidly drive the fiber end in and out of alignment with a cavity mirror, creating the conditions necessary for Q-switching. We investigate the effectiveness of different Q-switch configurations and analyze the Q-switch opening time of each configuration. [c] 2010 Optical Society of America OCIS codes: 060.2410, 060.3510, 140.3500, 140.3510, 140.3540.

We propose a sequence of transmission and reflection measurements that makes it possible to get a relatively accurate estimate for refractive index of optically isotropic powder materials. This method makes use of immersion liquids and a multifunction spectrophotometer, which we have constructed recently. As an example we present data for Ca[F.sub.2]. OCIS codes: 120.0120, 120.1840, 260.2030.

Performance of a fiberoptic system depends on the coupling efficiency and the alignment retention capability. A fiberoptic system experiences performance degradation due to uncertainties in the alignment of the optical fibers with the laser beam. The laser devices are temperature sensitive, generate large heat fluxes, are prone to mechanical stresses induced and require stringent alignment tolerance due to their spot sizes. The performance of an optoelectronic system is also affected by many other factors such as geometric tolerances, uncertainties in the properties of the materials, optical parameters such as numerical aperture, etc. To analyze such a complex system, we need to understand the inter-relationships between various elements that together make the complex system. In this paper, we apply systematic, formal procedures for identifying the relationships between the critical system level parameters through system decomposition strategies. We have included the sensitivity of the variables with respect to the functions to assist in the system decomposition. We apply graph partitioning strategies to decompose the system into different subsystems. We also demonstrate system decomposition technique using a simple to implement simulated annealing algorithm. The results of system decomposition using graph partitioning technique and simulated annealing are also compared. [DOI: 10.1115/1.2056573]

Compressive radial stress on the glass fiber has caused microbending losses and hence microbending losses in double-coated optical fibers that are caused by axial strain-induced creep deformation of polymeric coatings are examined. The thickness and YoungEs modulus of the secondary coatings should be large enough to withstand an external mechanical force when the thickness and physical properties of the polymeric coating are chosen to minimize the microbending loss.

A combined probe microscope, a scanning probe near-field optical microscope (SNOM) combined with Kelvin probe force microscope (KFM) that uses a slim and bent optical fiber probe (S/B fiber probe), is developed. Near-field photoexcitation is performed on [Alq.sub.3] thin films through the S/B fiber probes and the spatial pattern of photoinduced reduction in surface potential (SP) is envisioned by KFM measurement with the same probe.

The electromechanical responses of a piezocoated optical fiber subjected to time-harmonic excitation of mechanical load as a sensor or to electric voltages as an actuator are examined. The equations of motion under dynamic excitations are solved, by using proper boundary conditions to produce the analytical forms of the integrated systemEs electromechanical responses.

The mode conversion of a laser in a metal coated fiber, from transverse magnetic (TM) mode to surface plasma wave, is examined. The surface plasma wave undergoes surface enhanced Raman scattering when the metal surface has metallic particles attached to it and molecules are adsorbed on them.