Evanescent wave cavity ring-down spectroscopy (EW-CRDS) is described. The total internal reflection (TIR)-ring and monolithic folded cavity designs are briefly discussed. The performance of EW-CRDS for trace water vapor detection is evaluated by accounting for surface chemical and physical properties as well as intrinsic resonator properties. INTRODUCTION Cavity ring-down spectroscopy (CRDS) us...

We have doubled the frequency of a single mode distributed Bragg reflection (DBR) semiconductor laser. The laser is optically locked to an external enhancement ring resonator that contains an antireflection coated potassium niobate crystal. Unlike Fabry-Perot cavity lasers the DBR laser is found to operate in only one longitudinal mode and allows stable second harmonic generation. We present th...

We report on a highly efficient waveguide resonator device for the production of 775 nm light using a titanium indiffused LiNbO3 waveguide resonator. The device stably produces up to 110 mW of second harmonic power with 140 mW incident on the device an external conversion efficiency of 75%. The cavity length is also locked, using a Pound-Drever-Hall type locking scheme, via one of two methods i...

A new approach for stable intra-cavity phase locking of several laser channels is presented. In this approach, special interferometric couplers are incorporated inside a laser resonator to obtain efficient self phase-locking between separate laser channels. We analyze the approach and demonstrate experimentally phase-locking of two and of four laser channels, that are derived from Nd:YAG lasers...

This thesis describes a theoretical and experimental investigation of the intensities, linewidths, and frequencies of radiation by an atom in an optical resonator. It is found that the atom's spontaneous emission rate may be enhanced or inhibited, depending on the tuning of the resonator, and its transition frequencies shifted. A simple classical description of these effects is given in which t...

This paper reports on the results of research into passively modelocked fiber laser with a record-setting optical length of the resonant cavity amounting to 3.8 km. Significant elongation of the laser resonator led to more than two orders of magnitude increase in the output pulse energy at the same pump radiation power. At ultra-low (for mode-locked lasers) pulse repetition rate (77 kHz) and pu...

Wave mixing with a self-induced grating in a saturable absorber, which is inserted into a resonator, gives special filtering behavior. In a linear Fabry-Perot cavity with gain, the grating forms a self-matched, threemirror laser cavity that can discriminate between modes whose frequency difference is much lower than the grating bandwidth. The effect was used to obtain single-mode lasers with na...

Imperfections in the surface of intracavity elements of an optical ring resonator can scatter light from one mode into the counterpropagating mode. The phase-locking of the cavity modes induced by this backscat-tering is a well-known example that notoriously afflicts laser gyroscopes and similar active systems. We experimentally show how backscattering can be circumvented in a unidirectionally ...

We show how a passive image-rotating optical resonator can be used to convert a linearly polarised, lowest-order Gaussian beam into a radially polarized beam. The image and polarization rotation of the cavity removes the frequency degeneracy of the modes, making it possible to select the radially polarized mode by cavity tuning. With the addition of gain, the same cavity should operate as a rad...

We design and demonstrate a compact, narrow-linewidth integrated laser based on low-loss silicon nitride waveguides coupled to a III-V gain chip. By using a highly confined optical mode, we simultaneously achieve compact bends and ultra-low loss. We leverage the narrowband backreflection of a high-Q microring resonator to act as a cavity output mirror, a single-mode filter, and a propagation de...