High Harmonic Generation is a non-linear process that enables the tabletop production of coherent laser-like beams in the extreme ultraviolet and soft x-ray regions of the electromagnetic spectrum. In order to achieve significant high harmonic flux, the generated high harmonics must be phase matched. We achieve this by coupling the incident driving laser into a hollow cylindrical waveguide. The...

ABSTRACT To improve the Mid-Infrared (IR) chemical sensing capabilities in liquids and gases, a polymer based waveguide that has 100% interaction with Quantum Cascade (QC) laser field is proposed and demonstrated. The waveguide has thickness down to 10s nanometers so that chemical diffusion and preconcentration could happen very fast; the path length is increased from several microns to over ce...

We report the demonstration of a one-dimensional waveguide for terahertz quantum-cascade (QC) lasers, which acts as a leaky-wave antenna and tailors laser radiation in one dimension to a directional beam. This scheme adapts microwave transmission-line metamaterial concepts to a planar structure realized in terahertz metal-metal waveguide technology. The active leaky-wave antenna is fed by a mas...

Room-temperature continuous-wave ~cw! operation is demonstrated with InGaN multiple-quantum-well laser diodes containing an asymmetric waveguide structure. Pulsed threshold current densities as low as 5.2 kA/cm have been obtained for ridge-waveguide laser diodes grown on sapphire substrates by metal-organic chemical vapor deposition. For improved thermal management, the sapphire substrate was t...

The fabrication of an ion-exchanged waveguide beam deflector containing a photowritten grating is described. The planar waveguide was fabricated by thermal K(+) exchange in a borosilicate glass. The grating was written by photobleaching an absorption defect centered at 330 am, which was created by gamma-ray irradiation of the glass. The bleaching was accomplished with the 351-nm line from an ar...

We present details of the homo-epitaxial growth of Yb:YAG onto a <100> oriented YAG substrate by pulsed laser deposition. Material characterization and initial laser experiments are also reported, including the demonstration of laser action from the 15 μm-thick planar waveguide generating 11.5 W of output power with a slope efficiency of 48%. This work indicates that under appropriate condition...

Hollow glass waveguides with a 250-µm i.d. have been fabricated with a liquid-phase deposition technique that uses silica tubing as a base material. The losses of the 250-µm-bore guide measured at CO(2) laser wavelengths are as low as 2.0 dB/m. The straight losses for the hollow guides are in good agreement with theoretically predicted losses as a result of the nearly ideal structure of the gui...

We demonstrate a diode-pumped femtosecond-laser-inscribed Yb:YAG channel waveguide laser, Q-switched by using single-walled carbon nanotubes (SWCNTs) near 1029 nm. We used saturable absorber mirrors (SAMs) fabricated by depositing SWCNTs on three different output couplers. Best performance of the 9.3-mm-long ultra-compact Q-switched waveguide laser is obtained with an output coupling transmissi...

To achieve a high-power single-transverse mode laser, we here propose supersymmetry-based triple-ridge waveguide semiconductor laser structure, which is composed of an electrically pumped main broad-ridge located in the middle and pair lossy auxiliary partner waveguides. The waveguides are designed to provide dissipative modes that can phase match couple with higher-order waveguide. By appropri...