The aim of the lecture is to gain inside into current research topics in semiconductor laser physics. After introducing the fundamentals of laser gain media and cavities (including mode selection concepts), state-of-the-art devices will be presented and discussed in detail.
Based on this, we will focus on two interesting current research topics starting with mid-IR (MIR) frequency combs based on semiconductor lasers. The second case will deal with concepts of MIR-lasers (mainly Quantum/Interband Cascade Lasers) and –detectors for application in ultra-sensitive spectroscopic techniques.

1. Fundamentals of Semiconductor Lasers I – Gain media
   - Optical Transitions in Semiconductors
   - Important Non-Radiative Scattering Processes
   - Rate Equation Models
   - Discussion of Semiconductor Gain Media: Diode Lasers, Quantum Well Lasers,
      Quantum Cascader Lasers, Interband Cascade Lasers
2. Fundamentals of Semiconductor Lasers II - Cavities and Mode Selection
   - Laser Cavities
   - Concepts for Single Mode Emission: EC, DBR, DFB (Different Orders) &
     Photonic Crystals
   - Thermal Management and High-Frequency Optimization Techniques
3. Mid-Infrared Optoelectronics
   - State-of-the-art and Novel Materials
   - QW Lasers, Quantum Cascade Lasers vs Interband Cascade Lasers
   - Photodiode, QWIP & QCD
4. Frequency combs
   - Multimode Lasing
   - Active and Passive Mode Locking (Short Pulse generation)
   - Mid-Infrared Frequency Combs
5. Applications of Semiconductor Lasers (2 units)
   - Basics of MIR-Spectroscopy (Gases vs. Liquids)
   - Absorption Spectroscopy
   - Overview of Laser-based Spectroscopic Techniques (Cavity-Enhanced Techniques,
      Laser Dispersion Spectroscopy, Dual-Comb Spectroscopy)

Lecture period: Thu 2-4pm starting October 11

preliminary discussion: Mo, October 8, 3-4 pm

if you are interested send an email to Benedikt Schwarz and/or Borislav Hinkov

change of date is possible and will be discussed at October 8.

oral exam

Semiconductor physics and photonics