A formula for the laser linewidth of arbitrary cavities in the multimode nonlinear regime is derived from a scattering analysis of the solutions to semiclassical laser theory. The theory generalizes previous treatments of the effects of gain and openness described by the Petermann factor. The linewidth is expressed using quantities based on the nonlinear scattering matrix, which can be computed...

We present measurements of the acoustic vibrations of single gold nanorods deposited on a glass substrate immersed in air and water by ultrafast pump-probe spectroscopy. The nanorods display two vibration modes, the breathing mode and the extensional mode. The damping time of the two modes is influenced by the environment, and a reduction of the quality factor is observed when the particles are...

We describe a fabrication technique for double-paddle oscillators based solely on wet etching, resulting in quality factors up to 8 ·105 at room temperature and in vacuum. The quality factor achieved is the highest demonstrated so far at room temperature. The fabrication procedure, not involving any dry etching step, represents a valid and low cost alternative to the other techniques previously...

We developed a method to fabricate an array of silver non-planar nano-arc-gaps via inverted hemispherical colloidal lithography and shadow metal evaporation methods. It is found that there is a localized surface plasmon mode which results in extraordinary optical transmission. The electric field is strongly localized at the nano-arc-gap region and therefore induces a resonance that has an ultra...

We performed laboratory and numerical modeling studies of an optical parametric oscillator with 90 degrees intracavity image rotation. We found that the signal beam was more symmetric than that from comparable cavities without image rotation, and it had low values of the beam quality factor, M(2) . Oscillator performance agreed well with our numerical model.

Abstract: In this paper a novel radial stub feeding microstrip bow-tie antenna is designed to operate between C and X band and its performance characterization is presented. This antenna is having simple structure and topology over other stub loaded antennas. In addition the proposed antenna adjusts to the desired frequency easily. Antenna output parameters like radiation pattern, axial ratio, ...

A method is presented to calculate the quality factor ( ) of small antennas, which is based on the understanding that for a small antenna the total energy in Poynting theorem can be easily separated into the stored energy and radiated energy by using the low frequency expansions. The Poynting theorem in frequency domain provides an equation on the stored electric and magnetic energy while the P...

In this report, we propose a photonic crystal heteroslab-edge microcavity design for optical index sensing, where the high quality Q surface mode is confined by mode-gap effect. By optimizing the barrier region of the microcavity, high Q factor of 6.6 105 is obtained in simulations. Lasing actions with high Q factor and low threshold of 6400 and 0.55 mW are obtained from the real devices. High ...

We propose and analyze a new photonic crystal cavity design that supports a dipole mode with a quality factor greater than 20,000. Such a high quality factor is obtained by precise tuning of the cavity length with minimal disruption of the surrounding photonic crystal. A fabrication procedure based on dry etching of InGaAsP material in HI/H2/Ar is used to demonstrate photonic crystal lasers wit...

We have measured the mechanical dissipation in a sample of fused silica drawn into a rod. The sample was hung from a multiple-bob suspension, which isolated it from rubbing against its support, from recoil in the support structure, and from seismic noise. The quality factor, Q, was measured for several modes with a high value of 57 million found for mode number 2 at 726 Hz. This result is about...