A5102747746- Spectroscopy and Laser Applications
- Photonic and Optical Devices
- Electromagnetic Simulation and Numerical Methods
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Laser Technologies
- Optical Network Technologies
- Quantum Information and Cryptography
- Neural Networks and Reservoir Computing
- Theoretical and Computational Physics
- Electromagnetic Scattering and Analysis
- Muscle Physiology and Disorders
- Muscle activation and electromyography studies
- Terahertz technology and applications
- Atmospheric Ozone and Climate
- Microwave Engineering and Waveguides
- Quantum and electron transport phenomena
- Advanced Numerical Methods in Computational Mathematics
- Semiconductor Quantum Structures and Devices
- Genetic Neurodegenerative Diseases
- Laser Design and Applications
- Laser-Matter Interactions and Applications
Technical University of Munich
1973-2024
We present a full-wave Maxwell-density matrix simulation tool including c-number stochastic noise terms for the modeling of spatiotemporal dynamics in active photonic devices, such as quantum cascade lasers and dot structures. The coherent light–matter interaction devices plays an important role generation frequency combs other nonlinear non-classical optical phenomena. Since emergence features is directly linked to properties, detailed simulations characteristics are required development...
Portable terahertz (THz) frequency comb sources are highly desired for applications in rotational molecular spectroscopy and sensing. To date, direct THz quantum cascade laser (QCL) generation is not achievable at room temperature. However, based on intracavity difference (DFG) mid-infrared (mid-IR) QCLs a promising alternative. Here, we present numerical study of DFG-QCL formation mid-IR self-consistent multi-domain simulation approach. The dynamical simulations performed using our...
Focusing on two-level atoms, we apply the positive $P$ representation to a full-wave mixed bosonic and fermionic system of Jaynes-Cummings type identify an advantageous degree freedom in choice involved nonorthogonal basis states. On this basis, propose stochastic correction Maxwell-Bloch equations by relating them differential equation nonclassical phase space, which captures full second quantization dynamics system. This approach explores connection between semiclassical field-quantized...
Terahertz (THz) quantum cascade lasers (QCL) may operate as harmonic frequency combs, exhibiting a mode-separation of multiple times the round trip frequency. This work aims to shed light on coupled field-electron dynamics that lead mode-locking in defect-engineered THz QCLs. Therefore, we use Maxwell-Bloch equations describing medium two-level systems interacting with electric field laser cavity. We find both amplitude and phase are introduced defects, system quickly reaches locked state....
Often described as the quantum mechanical counterpart to classical random walk, walk is characterized by a ballistic spread of spatial particle probability distribution, with fundamental implications well practical relevance, e.g., for algorithms. Recently, it has been shown that optical frequency combs can mimic behavior walk. This "quantum comb" induced injection radio (RF) signal into ring-shaped, mid-infrared cascade laser (QCL). Here, we report on compact and accurate extension...
Focusing on two-level atoms, we apply the positive representation to a full-wave mixed bosonic and fermionic system of Jaynes-Cummings type identify an advantageous degree freedom in choice involved nonorthogonal basis states.On this basis, propose stochastic correction Maxwell-Bloch equations by relating them differential equation nonclassical phase space, which captures full second quantization dynamics system.This approach explores connection between semiclassical field-quantized...
Harmonic and sub-harmonic RF injection locking is demonstrated in a terahertz (THz) quantum-cascade vertical-external-cavity surface-emitting laser (QC-VECSEL).By tuning the frequency around integer multiples submultiples of cavity round-trip frequency, different harmonic subharmonic orders can be excited same device.Modulation-dependent behavior device has been studied with recorded lasing spectral broadening bandwidths each case.In particular, results observation spectra over 200 GHz.A...
In a laser, the control of its spectral emission depends on physical dimensions optical resonator, limiting it to set discrete cavity modes at specific frequencies. Here, we overcome this fundamental limit by demonstrating monolithic semiconductor laser with continuously tunable repetition rate from 4 up 16 GHz, employing microwave driving signal that induces spatiotemporal gain modulation along entire cavity, generating intracavity mode-locked pulses group velocity. At output, frequency...
Perfectly matched layer (PML) boundary conditions have been used for several decades the simulation of open domains within finite difference time domain (FDTD) method. In this paper, we report on a new PML-based partially reflecting condition generalized Maxwell-Bloch equations that enables setting certain value reflectance R at end domain. To evaluate performance method, present an error analysis and results real optoelectronic device.
We present a full-wave Maxwell-density matrix simulation tool including c-number stochastic noise terms for the modeling of spatiotemporal dynamics in active photonic devices, such as quantum cascade lasers (QCLs) and dot (QD) structures. The coherent light-matter interaction devices plays an important role generation frequency combs other nonlinear nonclassical optical phenomena. Since emergence features is directly linked to properties, detailed simulations characteristics are required...
The generation of terahertz (THz) frequency comb emission by intracavity difference (DFG) in a mid-infrared (mid-IR) quantum cascade laser (QCL) is promising alternative to direct THz QCL generation. Concerning their room temperature operation capabilities, these devices are well suited for applications rotational molecular spectroscopy and sensing. In order better understand the second-order nonlinear mixing process required generation, we present an extensive analysis such DFG-QCL using...