Active Region Overheating in Pulsed Quantum Cascade Lasers: Effects of Nonequilibrium Heat Dissipation on Laser Performance.

Mid IR Quantum cascade lasers are of high interest for the scientific community due to their unique applications. However, the QCL designs require careful engineering to overcome some crucial disadvantages. One of them is active region (ARn) overheating, which significantly affects laser characteristics, even in the pulsed mode.

High-Power Quantum Cascade Lasers Emitting at 8 μm: Technology and Analysis.

In this work, we demonstrate the features of a two-stage epitaxial growth technique and show the results of power and efficiency measurements for three different designs of quantum cascade lasers with a record-high peak power in the 8 μm spectral region. The time-resolved QCL spectral study proves that InP-based upper cladding paired with an InP contact layer provides better heat dissipation and allows one to reach better power characteristics in comparison with InGaAs-based contact, even with short pulse pumping.

Comparison of prognostic scales for patients with metastatic spine disease.

This is one-centre retrospective study with the aim to identify the scale, which provides the most accurate prediction of life expectancy in patients with metastatic lesions in spine. A retrospective analysis of clinical data of 138 patients with metastatic spinal tumors. Patients underwent spinal cord decompression and instrumented stabilization of affected area.