Optical feedback in a vertical-cavity surface-emitting laser due to fiber facet of varying position is studied experiment and theory. Measured spectra light-current curves show periodic variations resonant wavelength, threshold current, differential quantum efficiency, output power as function position. Theoretical results were obtained using 2 /spl times/ vector propagation matrix method which models the single structure shows good agreement with experimental results. A novel for...

Longitudinal spatial hole burning (SHB) in semiconductor lasers is examined theoretically and experimentally index-coupled distributed-feedback (DFB) lasers. The amplified spontaneous emission (ASE), or facet light, below threshold measured fitted by a theoretical model order to extract the parameters such as phases of optical field reflection at facets. ASE spectrum above also compared with results using same parameters. photon density profile dominant lasing mode carrier bias current are...

Dual-pump four-wave mixing for wavelength conversion is demonstrated using a distributed-feedback laser integrated with two electroabsorption modulators. The device acts as both the medium and dual-pump source. For given input probe signal, output conjugate signal-to-noise ratio values of greater than 10 dB were measured over wavelengths ranging from 1557 to 1564 nm probe-conjugate detuning 0.5 nm.

A distributed-feedback (DFB) laser with a curved waveguide in the active region integrated an electroabsorption modulator is studied experimentally and theoretically. The controls lasing wavelength of DFB by acting as optical phase shifter. Our model, which based on transfer matrix method, used to simulate this multisection device waveguide, self-consistently including effects spatial hole burning (SHB). model explains features wavelength-tuning behavior spectrum shows good agreement...

A laser opening technique is employed as the photolithography process to form selective emitter (SE) structures on multi-crystalline silicon (mc-Si) substrates for large-area (156×156 mm2) solar-cell industry. The best efficiency of 16.35% obtained with developed SE structure after a damage removal optimisation heavily and lightly doped dopants, which yields gain 0.88% absolute compared that reference cell. Significantly, mc-Si solar cell without can also reach 0.48% absolute. has...

Abstract We developed a Monte‐Carlo‐based radiative heat transfer model capable of simulating solar exposure and subsequent warming rough snow ice surfaces on ice‐covered airless system bodies. The accounts for wavelength‐dependent internal light scattering conduction in the interior down to meter‐scale depths. validated against analytical experimental test cases with relevant applications Europa, one Jupiter's moons. examined differential heating across surface, from centimeter meter scale,...

We report on the tunable dual-mode operation of a chirped grating distributed-feedback (DFB) laser device with two integrated modulators which act as tuning sections. A transfer-matrix model is used to simulate amplified spontaneous emission spectrum for DFB laser. Several types are observed wavelength spacings 0.5 nm and 1.4 corresponding frequency detunings 63 GHz 175 GHz.

We demonstrate a compact, all-optical XOR gate at 1550nm by integrating three symmetric self-electooptic effect devices (S-SEEDs) with micro-optics. Each S-SEED operates as NAND or NOR and can switch faster than 10ps.

The impact of Foreign Material (FM) on the semiconductor manufacturing process is well established. For organic corrosive FM that are embedded in final devices after assembly, FTIR one preferred characterization techniques by fingerprint identification or database searching. This technique becomes more challenging for smaller feature sizes where strong IR interferences complicated matrices impedes adequate identification. Advances mapping ATR-FTIR can push lateral sampling resolution to...

We describe recent advances in the development of 1550-nm symmetric self-electrooptic effect devices (S-SEEDs). S-SEEDs are semiconductor optoelectronic used to implement ultrafast all-optical logic functions for optical fiber communication applications. In this paper, basic S-SEED operation is described, followed by a detailed explanation optimization techniques improve DC and high-speed performance these long wavelength devices. Both epitaxial strain quantum well design shown be important...

Results are presented showing the effect of bias current on mode competition in large-signal modulation response a vertical-cavity surface-emitting laser. The overshoot and turn-on delay between LP01 LP11 modes observed to be strongly dependent relative individual threshold currents both experiments simulations.

We demonstrate the operation of low-power reflective S-SEEDs with 6-ps switching times at a 2-volt bias. Efficient refractive micro-optics are used to optically interconnect multiple S-SEED gates. The technology platform is expected enable dense photonic logic circuits for high-speed telecommunications-related applications.

Summary form only given. We investigate a new technique to perform wavelength conversion, cross-absorption modulation (XAM), where modulated pump signal is used change the absorption of modulator so that output DC probe also modulated, and non-inverted conversion from achieved. High-speed at 20 Gb/s over 30 nm has been reported recently using this in single electroabsorption (EA) modulator. Here, we use an integrated multiple-quantum-well modulator/laser (EML), laser section acts as probe,...

Summary form only given. We describe an improved method for measuring the spontaneous emission (SE) spectra from cleaved side of a VCSEL cavity using 62.5-/spl mu/m multimode fiber and present experimental results. The under study was grown fabricated in AlGaAs/GaAs material system. advantage this is that distortion due to top transmission measurements through distributed Bragg reflectors filters avoided. Furthermore, by integrating SE spectrum rather than directly power, we ensure indeed...

This paper describes technologies developed at Sandia National Laboratories to support a joint DoD/DoE initiative create compact, robust, and affordable photonic proximity sensor for munitions fuzing. The fuze employs high-power vertical-cavity surface-emitting laser (VCSEL) arrays, resonant-cavity photodetectors (RCPDs), refractive micro-optics that are integrated within microsensor whose volume is approximately 0.01 cm³. Successful development integration of these custom...

Abstract not Available.

A novel method for fabricating AIGaAs microstructures is investigated. The process consists of a thermal volume oxidation AIGaAs/GaAs epitaxy and selective etching the resulting aluminum oxide.

We study optical-feedback effects using an integrated laser-modulator/amplifier. Our experiment and theory are agree well provide interesting results of feedback on optical spectrum, spatial-hole burning, the photon density profile, microwave modulation.

Monolithically-integrated optical gain-competition inverters are demonstrated at 1.55 μm in the InGaAsP/InP material system. The consist of etched-facet slave lasers that side-injected with tapered etchedfacet master lasers. Single-input show improved quenching contrast for devices larger taper width respect to laser length. Inverter performance also shows a dependence on ridge and lasing modes laser. Two-input characterized which demonstrate NAND NOR logic operation different currents.