Operation of a far-infrared (1.5–4.2 THz) p-Ge laser in an open quasi-optical resonator is demonstrated. This contrasts with previous designs where mirrors were fixed to surfaces of the active crystal. Enhanced stability and tuning of the laser cavity length are demonstrated, which are steps toward continuous tunability without mode-hops. 2002 Elsevier Science B.V. All rights reserved. PACS: 42...

We used the high-precision laser interferometer technique of power recycling to characterize the optical loss of an all-reflective grating beam splitter. This beam splitter was used to set up a Michelson interferometer with a power-recycling resonator with a finesse of 883. Analyzing the results obtained, we determined the beam splitter's total optical loss to be (0.193+/-0.019)%. Low loss all-...

In extension to known concepts of wavelength-multiplexing diode laser arrays, a new external cavity is presented. The setup simultaneously improves the beam quality of each single emitter of a standard 25 emitter broad-area stripe laser bar and spectrally superimposes the 25 beams into one. By using this external resonator in an "off-axis" arrangement, beam qualities of Mslow2<14 and Mfast2<3 w...

We show theoretical and experimental results from a tunable laser, with its center wavelength in the C-band, designed using coupled-ring resonator mirrors. The effective cavity length enhancement and negative optical feedback obtained from the resonators helps to narrow the laser linewidth in a small form factor. We report a linewidth of 160 kHz and a side-mode suppression ratio of 9 40 dB over...

An analysis of transverse laser resonator modes is presented, based on a recently developed coherence theory in the space-frequency domain. The modes are introduced by means of solutions of an integral equation that expresses a steady-state condition for a second-order correlation function of the field across a mirror of the laser cavity. All solutions of this integral equation are found to be ...

We combine the sensitivity advantages of cavity ring-down spectroscopy (CRDS) with the versatility of optical fiber sensing technology in a spatially extended passive fiber ring resonator constructed of common telecommunications components. The resonator is characterized with both pulsed and continuous-wave diode laser excitation, and it is shown to be a practical device for direct measurement ...

We develop a method for fabricating very small silica microbubbles having a micrometer-order wall thickness and demonstrate the first optical microbubble resonator. Our method is based on blowing a microbubble using stable radiative CO(2) laser heating rather than unstable convective heating in a flame or furnace. Microbubbles are created along a microcapillary and are naturally opened to the i...

A novel resonator is proposed, in which the polarizing properties of standard grating and polarizing components (such as Brewster angle windows) inside the cavity are used to vary continuously the ouput coupling over a wide range of values. An analysis of the polarization properties of the modes of such a resonator is presented, and practical suggestions are made about the choice of the polariz...

A new approach for efficient second-harmonic generation using diode lasers is presented. The experimental setup is based on a tapered amplifier operated in a ring resonator that is coupled to a miniaturized enhancement ring resonator containing a periodically poled lithium niobate crystal. Frequency locking of the diode laser emission to the resonance frequency of the enhancement cavity is real...