A5023447239- Semiconductor Lasers and Optical Devices
- Semiconductor Quantum Structures and Devices
- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Molecular Junctions and Nanostructures
- GaN-based semiconductor devices and materials
- Spectroscopy and Quantum Chemical Studies
- Laser-Matter Interactions and Applications
- Spectroscopy and Laser Applications
- 2D Materials and Applications
- Solid State Laser Technologies
- Advanced Semiconductor Detectors and Materials
- Perovskite Materials and Applications
- Advanced Chemical Physics Studies
- Chalcogenide Semiconductor Thin Films
- Quantum and electron transport phenomena
- Optical Network Technologies
- Quantum Dots Synthesis And Properties
- Laser Design and Applications
- Semiconductor materials and devices
- Terahertz technology and applications
- Semiconductor materials and interfaces
- Acoustic Wave Resonator Technologies
- Phase-change materials and chalcogenides
- Optical properties and cooling technologies in crystalline materials
Nonlinear Control Strategies (United States)
2013-2024
University of Arizona
2015-2024
Philipps University of Marburg
1996-2023
Optical Sciences (United States)
2002-2018
United States Air Force Research Laboratory
2009-2018
Arizona State University
2018
University of New Mexico
2018
Arizona Science Center
2005-2011
U.S. Air Force Research Laboratory Sensors Directorate
2009
Oracle (United States)
2007
A report is presented on an optically-pumped semiconductor disk laser providing a continuous-wave output power of 106 W at heatsink temperature 3 °C. The laser, which operates in the transversal multimode regime, emits wavelength 1028 nm. This high achieved by carefully optimising chip design, growth process, and bonding layer.
Fully microscopic many-body models are used to study the importance of radiative and Auger carrier losses in InGaN∕GaN quantum wells. found be negligible contrast recent speculations on their for experimentally observed efficiency droop. Good agreement with measured threshold is demonstrated. The results show no significant dependence details well alloy profile.
The temperature dependence of the measured internal efficiencies green and blue emitting InGaN-based diodes is analyzed. With increasing temperature, a strongly decreasing strength loss mechanism responsible for droop found which in contrast to usually assumed behavior Auger losses. However, experimental observations can be well reproduced assuming density activated defect recombination with independent time.
The influence of propagation on the nonperturbative high-harmonic features in long-wavelength strong pulse excited semiconductors is studied using a fully microscopic approach. For sample lengths exceeding wavelength exciting light, it shown that effectively acts as very additional dephasing reduces relative height emission plateau up to six orders magnitude. This induced clarifies need use extremely short polarization decay times for quantitative analysis experimental observations.
Abstract We identify a quantum well internal high density Augerlike loss process as the origin of so called ‘droop’ efficiency (IQE) in InGaN based light emitters. The IQE such device peaks at small current densities and then monotonously decreases towards higher currents. this has been widely discussed recently many possible mechanisms have proposed for explaining effect. compare temperature carrier dependent electroluminescence photoluminescence measurements green emitting single...
We report an all-solid-state laser system that generates over 200 mW cw at 244 nm. An optically pumped semiconductor is internally frequency doubled to 488 The nm output coupled external resonator, where it converted using a CsLiB(6)O(10) (CLBO) crystal. power limited by the available nm, and no noticeable degradation in was observed period of several hours.
We report on the development of a high-power tunable yellow-orange laser. It is based intracavity frequency doubling widely tunable, highly strained InGaAs-GaAs vertical-external-cavity surface-emitting laser operating near 1175 nm. Over 5 W continuous-wave output power achieved and over 15-nm band centered at 587 This compact low-cost provides an innovative alternative for sodium guidestar lasers, medical communication applications.
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> We demonstrate near-diffraction limited (<formula formulatype="inline"> <tex Notation="TeX">${M} ^{2}\approx 1.5$</tex></formula>) output up to 23.8 W with optical-to-optical efficiency 27% and slope 32.4% 40.7 of multimode from an optically pumped semiconductor laser at 1040 nm. Temperature-dependent photoluminescence measurements confirm accurate epitaxial growth according the design thereby...
Semiconductor disk lasers have been shown to be ideal as wavelength-agile, high-brightness sources for producing high average power under various pulsed mode-locking scenarios. Systematic microscopic modeling reveals that ultrafast nonequilibrium kinetic hole burning in electron/hole carrier distributions dictates the outcome of femtosecond duration mode-locked pulse formation. The existence a large reservoir unsaturated carriers within inverted leads emergence multiple waveforms (not...
A fully microscopic approach is used to compute the losses in semiconductor lasers due spontaneous emission and Auger recombination. The model based on semiconductor-Bloch equations generalized quantum-Boltzmann type scattering second Born-Markov approximation. As input theory only needs structural layout fundamental bulk-bandstructure parameters. It demonstrated that such a comprehensive calculates gain/absorption, processes same level can reliably predict these usually dominant loss...
We report on the development and demonstration of tunable high-power high-brightness linearly polarized vertical-external-cavity surface-emitting lasers (VECSELs). A V-shaped cavity, in which antireflection-coated VECSEL chip (active mirror) is located at fold, a birefringent filter are employed to achieve large wavelength tuning range. Multiwatt cw TEM00 output with 20nm range narrow linewidth demonstrated room temperature.
A fully microscopic model is used to calculate the carrier losses in semiconductor lasers due Auger recombination and spontaneous emission. The results show that commonly assumed power-law dependencies of these loss processes on plasma density break down already below transparency point. Most significantly, dependent increase emission changes from quadratic linear, while reduced cubic approximately or even less.
Optical gain spectra of (GaIn)(NAs)/GaAs quantum-well lasers operating in the 1.3-μm-emission-wavelength regime are measured and compared to those a commercial (GaIn)(AsP)/InP structure. Good agreement experimental results with computed microscopic many-body theory is obtained. Due contributions second confined subband, spectrally broad region expected for at elevated carrier densities.
We report on a single frequency optically pumped semiconductor laser exhibiting an output power of 15 W in continuous wave operation. The GaAs-based structure presents emission wavelength 1020 nm and tuning range , with tunability 9 GHz. TEM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">00</sub> beam exhibits very low transverse phase fluctuations across the entire mode, leading to quality . A free-running linewidth 21 kHz has been deduced...
Anion substitution with bismuth (Bi) in III-V semiconductors is an effective method for experimental engineering of the band gap Eg at low Bi concentrations, particular gallium arsenide (GaAs). The inverse Bi-concentration dependence has been found to be linear concentrations x and dominated by a valence band-defect level anticrossing between As occupied p levels. This breaks down high where empirical models accounting only As-Bi interaction are not applicable. Predictive hybridization...
The dynamics of band-gap renormalization and gain build-up in monolayer MoTe$_2$ is investigated by evaluating the non-equilibrium Dirac-Bloch equations with incoherent carrier-carrier carrier-phonon scattering treated via quantum-Boltzmann type equations. For case where an approximately $300$ fs-long high intensity optical pulse generates charge-carrier densities regime, strong Coulomb coupling leads to a relaxation excited carriers on few fs time scale. pump-pulse generation induces large...
The capabilities of a fully microscopic approach for the calculation optical material properties semiconductor lasers are reviewed. Several comparisons between results these calculations and measured data used to demonstrate that yields excellent quantitative agreement with experiment. It is outlined how this allows one predict devices under high-power operating conditions based only on low-intensity photo luminescence (PL) spectra. Examples gain-, absorption-, PL- linewidth enhancement...
We report on the development and demonstration of a tunable, watt-level, blue-green, linearly polarized vertical-external-cavity surface-emitting lasers operating around 488nm by intracavity second-harmonic generation. By using lithium triborate crystal, we have achieved over 1.3W continuous wave blue-green power at with 5nm tunability.
We develop and demonstrate a multiwatt highly strained InGaAs∕GaAs vertical-external-cavity surface-emitting laser with free lasing wavelength of around 1170nm. This can be tuned from ∼1147to∼1197nm. low-cost compact agile potentially provide high-power coherent light in wide yellow-orange band by the intracavity frequency doubling.
The authors demonstrate the multiwatt linearly polarized dual-wavelength operation in an optically pumped vertical-external-cavity surface-emitting laser by means of intracavity tilted Fabry-Perot etalon and a Brewster window. sum frequency generation from lithium triborate crystal this confirms that these two wavelengths oscillate simultaneously. Over 30dB side-mode suppression can be achieved at dual with spectral spacing 2.1nm. output power is slightly reduced
Experimental gain spectra of 450 and 490 nm laser diodes on c-plane GaN are analyzed by detailed comparison with the results a fully microscopic theory. The calculation shows importance electron LO-phonon coupling. whole spectral shape, not only low energy tail, is strongly influenced contribution. inhomogeneous broadening parameter increases factor about two for cyan diode in blue structure. This indicates an increase alloy thickness fluctuations longer wavelength material.
The design and experimental realization of a type-II “W”-multiple quantum well heterostructure for emission in the λ &gt; 1.2 μm range is presented. photoluminescence spectra different excitation intensities are analyzed using microscopic theory. On basis good theory–experiment agreement, gain properties system computed semiconductor Bloch equations. Gain values comparable to those type-I systems obtained.