A5045724503- Advanced Fiber Laser Technologies
- Solid State Laser Technologies
- Photonic and Optical Devices
- Semiconductor Lasers and Optical Devices
- Photorefractive and Nonlinear Optics
- Spectroscopy and Laser Applications
- Photonic Crystal and Fiber Optics
- Semiconductor Quantum Structures and Devices
- Advanced Fiber Optic Sensors
- Laser-Matter Interactions and Applications
- Advanced Semiconductor Detectors and Materials
- Surface Roughness and Optical Measurements
- Optical and Acousto-Optic Technologies
- Optical Coatings and Gratings
- Laser Material Processing Techniques
- Phase-change materials and chalcogenides
- Advanced Frequency and Time Standards
- Advanced optical system design
- Silymarin and Mushroom Poisoning
- Advanced Measurement and Metrology Techniques
- Chalcogenide Semiconductor Thin Films
- Laser Applications in Dentistry and Medicine
- Optical Systems and Laser Technology
- Superconducting and THz Device Technology
University of Vienna
2019-2024
Christian Doppler Laboratory for Thermoelectricity
2019-2024
University of Neuchâtel
2024
FH Campus Wien
2020
We present a flexible all-polarization-maintaining (PM) mode-locked ytterbium (Yb):fiber laser based on nonlinear amplifying loop mirror (NALM). In addition to providing detailed design considerations, we discuss the different operation regimes accessible by this versatile architecture and experimentally analyze five representative mode-locking states. These states were obtained in 78-MHz configuration at intracavity group delay dispersion (GDD) values ranging from anomalous (-0.035 ps$^2$)...
We present high-reflectivity substrate-transferred single-crystal GaAs/AlGaAs interference coatings at a center wavelength of 4.54 μm with record-low excess optical loss below 10 parts per million. These high-performance mirrors are realized via novel microfabrication process that differs significantly from the production amorphous multilayers generated physical vapor deposition processes. This new enables reduced scatter due to low surface and interfacial roughness, while background doping...
Abstract For trace gas sensing and precision spectroscopy, optical cavities incorporating low-loss mirrors are indispensable for path length intensity enhancement. Optical interference coatings in the visible near-infrared (NIR) spectral regions have achieved total losses below 2 parts per million (ppm), enabling a cavity finesse excess of 1 million. However, such advancements been lacking mid-infrared (MIR), despite substantial scientific interest. Here, we demonstrate significant...
Tailoring the properties of driving laser to need applications often requires compromises among stability, high peak and average power levels, pulse duration, spectral bandwidth. For instance, spectroscopy with optical frequency combs in extreme/visible ultraviolet region a near-IR laser, therefore power, duration few tens fs, maximal available Contrarily, parametric conversion efficiency is higher for pulses 100-fs range due temporal walk-off coating limitations. Here we suggest an approach...
Dual-comb (DC) ranging is an established method for high-precision and high-accuracy distance measurements. It is, however, restricted by inherent length ambiguity the requirement complex control loops comb stabilization. Here, we present a simple approach expanding ambiguity-free measurement of dual-comb exploiting intrinsic intensity modulation single-cavity dualcolor DC simultaneous time-of-flight nd D C This enables distances up to several hundred km with precision accuracy dualcomb...
We present our results for simultaneous measurement of the refractive indices gallium arsenide (GaAs) and aluminum $({\mathrm{Al}}_{x}{\mathrm{Ga}}_{1\text{\ensuremath{-}}x}\mathrm{As})$ in spectral region from $2.0\phantom{\rule{0.16em}{0ex}}\textmu{}\mathrm{m}\phantom{\rule{0.16em}{0ex}}\mathrm{to}\phantom{\rule{0.16em}{0ex}}7.1\phantom{\rule{0.16em}{0ex}}\textmu{}\mathrm{m}$...
Abstract We present a simple method to develop compact, reliable, and robust free-running erbium single-cavity dual-comb (DC) laser via polarization multiplexing. The key features of our design include dynamic tuning in the difference repetition rates laser, long-term stability, use off-the-shelf components. Polarization multiplexing exploits fast slow axes fiber, while modelocking is achieved through nonlinear amplifying loop mirror scheme using readily available operates at rate around...
We present a compact, reliable, and robust free-running all-polarization-maintaining erbium (Er) single-cavity dual-comb laser generated via polarization multiplexing with gain sharing. Polarization exploits the fast slow axes of fiber, while modelocking is achieved through nonlinear amplifying loop mirror scheme using readily available components. The operates at repetition rate around 74.74 MHz tuning capability in difference rates from 500 Hz to 200 kHz. This tunability makes system more...
We demonstrate for the first t ime he v iability o f d ual-comb spectroscopy using a free-running polarization-multiplexed erbium dual-comb laser. For current laser parameters, we achieve an optical resolution of 4 . 152 GHz.
We present a robust, precise, and accurate method to simultaneously measure the refractive indices of two transparent materials within an interference coating. This is achieved by measuring both photometrically transmittance spectrum as-grown individual layer thicknesses thin-film multilayer structure. These measurements are used for TMM-based curve-fitting routine which extracts their measurement uncertainties via Monte-Carlo-type error propagation. demonstrate performance this approach...
We present our results for simultaneous measurement of the refractive indices gallium arsenide (GaAs) and aluminum (Al$_\mathrm{x}$Ga$_\mathrm{1-x}$As) from $2.0$ to $7.1\,\mathrm{\mu m}$ ($5000$ $1400\,\mathrm{cm^{-1}}$). obtain these values a monocrystalline superlattice Bragg mirror excellent purity (background doping $\leq 1 \times 10^{-14}\,\mathrm{cm^{-3}}$), grown via molecular beam epitaxy. To recover over such broad wavelength range, we fit dispersion model each material. In novel...
We present state-of-the-art mid-IR high-reflectivity low-loss mirrors at 4.55 µm based on substrate-transferred crystalline coatings. Transmission losses of 150 ppm and excess <50 are demonstrated via cavity-ringdown direct transmission measurements.
For trace gas sensing and precision spectroscopy, optical cavities incorporating low-loss mirrors are indispensable for path length intensity enhancement. Optical interference coatings in the visible near-infrared (NIR) spectral regions have achieved total losses below 2 parts per million (ppm), enabling a cavity finesse excess of 1 million. However, such advancements been lacking mid-infrared (MIR), despite substantial scientific interest. Here, we demonstrate significant breakthrough...
Substrate-transferred crystalline mirror coatings have improved the quality of high-finesse cavities by significantly reducing thermal noise contributions when compared to amorphous dielectric [1]. However recent work on coating GaAs/AlGaAs multilayers has drawn attention previously reported intrinsic birefringence [2]. We report temperature dependent measurement birefringent cavity mode splitting in an ultrastable optical (F∼300 000 at 1542 nm), comprised two mirrors fused silica substrates...
Accurate knowledge of the refractive index, <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$n$</tex> , optical materials is required for development many devices in visible (VIS), near- (NIR) and mid-infrared (MIR) spectral regions, such as lasers, light-emitting super-luminescent diodes, distributed Bragg reflectors (DBRs). Typically, shows a variability depending on deposition conditions, which motivates need routine characterization...
We fabricate and characterize substrate-transferred single-crystal mirror coatings with 9.33 ± 0.17 ppm of transmittance 4.27 0.52 excess optical loss, corresponding to a transmission-loss dominated reflectance 99.9986% at 4.45 µm.
We report a method to simultaneously measure the refractive index of two materials in as-deposited heterostructures by analysis FTIR spectra and extraction layer thicknesses via SEM, yielding excellent results for GaAs/AlGaAs DBR.
We present state-of-the-art mid-IR high-reflectivity low-loss mirrors at 4.55 μm based on substrate-transferred crystalline coatings. Transmission losses of 150 ppm and excess <50 are demonstrated via cavity-ringdown direct transmission measurements. © 2019 The Author(s)
We present state-of-the-art mid-infrared high-reflectivity low-loss mirrors at 4.54 µm based on substrate-transferred crystalline coatings. Transmission losses of ~145 ppm and excess <50 are demonstrated via cavity-ringdown, direct transmission, photothermal measurements.
Recently, substrate-transferred crystalline coatings (e.g. GaAs/AlGaAs multilayers) have emerged as a groundbreaking new concept for the fabrication of high-performance thin-film interference in mid-IR [1], circumventing limitations established material systems and ion-beam sputtering technology.
Pushing the boundaries of cavity-enhanced spectroscopy experiments in mid-IR is strongly tied to availability suitable frequency combs and mirror coatings with well-characterized properties. Recently, substrate-transferred crystalline (e.g. epitaxial GaAs/AlGaAs multilayers bonded on silicon substrates) have emerged as a groundbreaking new concept for fabrication high-performance thin-film interference mid-IR, circumventing limitations established material systems physical vapor deposition...
We present high-reflectivity substrate-transferred single-crystal GaAs/AlGaAs interference coatings at a center wavelength of 4.54 um with record-low excess optical loss below 10 parts per million. These high-performance mirrors are realized via novel microfabrication process that differs significantly from the production amorphous multilayers generated physical vapor deposition processes. This new enables reduced scatter due to low surface and interfacial roughness, while background doping...