A terahertz vertical-external-cavity surface-emitting-laser (VECSEL) is demonstrated using an active focusing reflectarray metasurface based on quantum-cascade gain material. The focusing effect enables a hemispherical cavity with flat optics, which exhibits higher geometric stability than a plano-plano cavity and a directive and circular near-diffraction limited Gaussian beam with M2</sup...

Driven primarily by scientific curiosity, but also by the potential applications of intense sources of coherent sound, researchers have targeted the phonon laser (saser) since the invention of the optical laser over 50 years ago. Here we fabricate a vertical cavity structure designed to operate as a saser oscillator device at a frequency of 325 GHz. It is based on a semiconductor superlattice g...

A novel transition structure based on Substrate Integrated Circular Cavity (SICC) is proposed in this paper. The design approach of the transition structure can also be used in other operating frequency. Good performance of flexibility and S-parameters were observed for the new transition structure. Different design tools were used to validate the design method.

Vertical cavity lasers (VCLs) are of great interest as low-cost, high-performance light sources for fiber-optic communication systems. They have a number of advantages over conventional edgeemitting lasers, including low power consumption, efficient fiber coupling and wafer scale manufacturing/testing. For high-speed data transmission over distances up to a few hundred meters, VCLs (or arrays o...

We have examined noise behavior and polarization correlations in the output of a pulsed, multitransverse-mode, vertical-cavity, surface-emitting laser (VCSEL). We have measured the output of the laser simultaneously in two orthogonal, linear polarizations as a function of drive current for pulse widths of 3 ns, 10 ns, and 30 ns. We present joint probability distributions for the number of detec...

We report on the fabrication and operation of the first electrically pumped 1.55m vertical-cavity laser array for wavelength-division-multiplexing applications. The array consisted of four channels operating between 1509 and 1524 nm. Wafer bonding was used to integrate GaAs–AlGaAs distributed Bragg reflectors with an InP–InGaAsP active region.

We report the experimental demonstration of tunable ultraslow light using a 1.55 um vertical-cavity surface-emitting laser (VCSEL) at room temperature. By varying the bias current around lasing threshold, we achieve tunable delay of an intensity modulated signal input. Delays up to 100 ps are measured for a broadband signal with modulation frequency of 2.8 GHz. With a VCSEL design optimized for...

We investigate the spatial structure of broad-area vertical-cavity regenerative amplifiers injected with a homogeneous beam. The emerging patterns have a predominantly sixfold rotational symmetry, verifying the recent prediction of formation of hexagons. The length scale is controllable by means of detuning and follows the prediction for tilted waves.

abstract: since the field of micro electromechanical systems (mems) continues to grow, the flow in micro devices have become an area that receives a significant attention. the microscopic flows are usually characterized by the knudsen number (kn). when the characteristic size of the particle decreases down to a value comparable to the mean free path of the molecules, the continuum assumption fa...