Field Activities of Lasers

Far Field Investigations on Quantum Cascade Lasers

Quantum cascade lasers (QCLs) are unipolar semiconductor lasers operating in the mid infrared region. Their emitted wavelength is defined by the separation of intersubband levels which can be tailored by band structure engineering. Due to the fact that the maximum conduction band offset in the GaAs/AlGaAs material system is 380 meV, the lowest directly accessible wavelength is roughly 7 μm. One...

Response of fiber lasers to an axial magnetic field.

An axial magnetic field induces circular birefringence in optical fibers, resulting in the rotation of the polarization angle for a linearly polarized input (Faraday effect). The rotation angle is linearly proportional to the magnitude of the applied field. Accurate measurements of the polarization angle variation provide a means for monitoring the magnetic field. The Faraday effect in optical ...

Dynamics of optical-field-ionized plasmas for x-ray lasers.

Near-Field Emission of Lead-Sulfide-Selenide Homojunction Lasers

A bstruct-Measurements of the near-field intensity dis ributions of .7 three lead-sulfide-selenide diode lasers operating near 4.8 pm have been made as a function of injection current. Localized emission in the near field exhibits peaked structure of full width from 5 to 10 pm for operation above threshold. From the dependence of the emission profiles on injection current estimates of 25 ...

Near-field evolution in strongly pumped broad area diode lasers

Many applications such as pumping of solid state lasers or ignition of explosives require high optical output powers during a short period. Pulsed operated diode lasers meet these requirements. They can be driven at elevated power levels, well above the ones specified for continuous wave (cw) operation. The optical near-field intensity of a diode laser in this operation regime is a key paramete...