A mixture of H2 and CH4 is passed over a hot-wire tungsten filament in a diamond thin film chemical vapor deposition reactor. The resulting CH radicals are measured in absorption using cavity ring-down spectroscopy (CRDS). The concentration of the CH radicals increases as the filament is approached. The rotational temperature measurements indicate a large temperature discontinuity between the f...

We present a novel slanted faces of thin-disk composite Yb:YAG YAG laser which is side-pumped by four non-symmetric hollow- ducts. The pump light distribution in the disk is modeled by using Monte-Carlo ray tracing method. The temperature distribution inside the crystal is calculated by taking into account either the concentration of Yb+3 ion or the different transmission of laser output coupl...

The quantum-cascade laser can be used as an infrared source for a small portable photoacoustic trace gas detector. The device that we describe uses a quantum-cascade laser without collimating optics mounted inside an acoustic resonator. The laser is positioned in the center of a longitudinal resonator at a pressure antinode and emits radiation along the length of the resonator exciting an axial...

Laser gyroscopes making use of the Sagnac effect have been used as highly accurate rotation sensors for many years. First used in aerospace and defense applications, these devices have more recently been used for precision seismology and in other research settings. In particular, mid-sized (∼ 1 m-scale) laser gyros have been under development as tilt sensors to augment the adaptive active seism...

We review and study the roles of quantum and classical fluctuations in recent cavity-optomechanical experiments which have now reached the quantum regime (mechanical phonon occupancy .1) using resolved sideband laser cooling. In particular, both the laser noise heating of the mechanical resonator and the form of the optically transduced mechanical spectra, modified by quantum and classical lase...

Grazing flow passing over the quiescent fluid inside the cavity of a Helmholtz resonator can excite the resonator. When the frequency of the instabilities within the shear layer is near the natural frequency of the resonator then flow-excited resonance will occur. This process causes self-sustained periodic oscillations of the flow over the orifice of the resonator. Quantitative numerical predi...

Fractional curl operator has been used to derive solutions to the Maxwell equations for fractional rectangular cavity resonator. These solutions to the Maxwell equations may be regarded as fractional dual solutions. Behavior of field lines and surface current density in fractional cavity resonator have been investigated with respect to the fractional parameter. Fractional parameter describes th...

We present a theoretical analysis of a novel cavity electromechanical system where a mechanical resonator directly modulates the damping rate kappa of a driven electromagnetic cavity. We show that via a destructive interference of quantum noise, the driven cavity can effectively act like a zero-temperature bath irrespective of the ratio kappa/omega_{M}, where omega_{M} is the mechanical frequen...

We describe a 'wet mirror' apparatus for cw cavity-enhanced absorption measurements with Bacteriochlorophyll a (BChla) in solution and show that it achieves the full sensitivity gain ( approximately 2.3 x 10(4)) afforded by the finesse (3.4 x 10(4)) and loss distribution of our optical resonator. This result provides an important proof-of-principle demonstration for solution-phase cavity-enhanc...

Prospects for reaching persistent entanglement between two spatially-separated atomic Bose–Einstein condensates are outlined. The system setup comprises two condensates loaded in an optical lattice, which, in return, is confined within a high-Q optical resonator. The system is driven by an external laser that illuminates the atoms, such that photons can scatter into the cavity. In the superradi...