The control of coherent electrons is becoming relevant in emerging devices as (semi-)ballistic transport is observed within nanometer semiconductor structures at room temperature. The evolution of a wave packet – representing an electron in a semiconductor – can be manipulated using specially shaped potential profiles with convex or concave features, similar to refractive lenses used in optics....

Ceramic YAG/Yb:YAG/YAG planar waveguide lasers were realized on continuous-wave and mode-locked operations. The straight waveguide, fabricated by non-aqueous tape casting and solid state reactive sintering, enabled highly efficient diode-pumped waveguide continuous-wave laser with the slope efficiency of 66% and average output power of more than 3 W. The influence of the waveguide structure on ...

We report on a time-resolved electro-optic sampling of the photocarrier-induced surface field dynamics by a midband gap probe beam from a femtosecond fiber laser. By measuring the ultrafast surface field variation, we are able to derive the undistorted terahertz wave form radiated from the semiconductor surface that is excited by the femtosecond laser pulses. The derived wave form agrees well w...

We report a study of a new class of organic semiconductor as an optical gain medium. We demonstrate amplification of violet light by use of stimulated emission in a solution of a first-generation bis-fluorene-cored semiconducting dendrimer. Amplification is also observed in the solid state by means of amplified spontaneous emission in an optically pumped dendrimer planar waveguide. Gains of 36 ...

A novel pulse-compression scheme is proposed and demonstrated for compressing weak picosecond pulses having energies as small as 0.1 pJ. A semiconductor-laser amplifier is shown to impose a nearlylinear frequency chirp on the pulse as a result of self-phase modulation occurring because of gain-saturation-induced index changes. The amplified chirped pulse can be compressed by passing it through ...

A model for the terahertz optical asymmetric demultiplexer ( ) TOAD is presented, and its performance is assessed. A numerical ( ) model of a semiconductor laser amplifier SLA used as a nonlinear element is also gï en. Results of SLA carrier density, switching window, pulse switching, and a comparison of phase modulation and power gain for a frame rate higher than the recombination are presente...

A single-chip photocurrent-driven wavelength converter operating at 10 Gbit=s is presented. The device consists of a monolithically integrated widely tunable transmitter and an optical receiver. The transmitter consists of a sampled grating DBR laser, electroabsorption modulator and semiconductor optical amplifier (SOA). The optical receiver includes a quantum-well pin photodetector and a set o...

We report a hybrid integrated external cavity laser by butt coupling a quantum dot reflective semiconductor optical amplifier and a silicon-on-insulator chip. The device lasers at 1302 nm in the O-band, a wavelength regime critical to data communication systems. We measured 18 mW on-chip output power and over 50dB side-mode suppression ratio. We also demonstrated open eye diagrams at 10 and 40 ...

This paper presents a multichannel, time-resolved picosecond laser ultrasound system that uses a custom complementary metal-oxide-semiconductor linear array detector. This novel sensor allows parallel phase-sensitive detection of very low contrast modulated signals with performance in each channel comparable to that of a discrete photodiode and a lock-in amplifier. Application of the instrument...

First investigations of photoacoustic (PA) spectroscopy (PAS) of methane using an antimonide semiconductor laser are reported. The laser fabrication is made in two steps. The structure is firstly grown by molecular beam epitaxy, then a metallic distributed-feedback (DFB) grating is processed. The laser operates at 2371.6 nm in continuous wave and at room temperature. It demonstrates single-mode...