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Since some pathologies, such as cardiovascular or tumour diseases, have become some of the main causes of morbidity worldwide, a huge interest in the development of preclinical devices for their study has aroused during the past years. Their fabrication is a key factor for the study of these illnesses and it is directly linked with their pathological knowledge, early diagnosis and improvement of treatment.
Laser Terahertz Emission Microscopy (LTEM) is a method which has been developed in order to study intrinsic carrier dynamics in semiconductors with a spatial resolution which is only limited by the wavelength of the incident fs laser [1]. More recently, it has been shown that the spatial resolution in a terahertz (THz) spectroscopy experiment can be improved even further by utilizing plasmonic coupling...
In the last few years several experimental and numerical results have been reported on the emergence of extreme events and instabilities in different laser configurations such as Raman fiber lasers, optically injected semiconductor lasers, laser diodes with optical feedback and mode-locked lasers [1-4]. Rogue events can however be expected in some of these systems due to the complex noise-driven processes...
Stimulated Raman scattering presents one of important trends in nonlinear optics enabling to generate Stokes-shifted radiation at frequencies that are not readily available from solid state lasers. This method is suitable also because the phase matching fulfilment isn't required. To get stable and efficient Raman generation of picosecond and even femtosecond ultra-short Stokes pulses, the method of...
Satellite-based laser-based remote sensing (lidar) of the atmosphere can be used for meteorology, atmospheric chemistry and climate change but requires high energy (100mJ-class) lasers with precision wavelength control. A high energy Alexandrite laser source is an interesting alternative to Nd:YAG in future Earth Observation missions with its added scientific benefit of broad wavelength tunability...
Many trivalent rare earth ions, such as praseodymium (Pr), samarium (Sm), terbium (Tb) and dysprosium (Dy), have radiative transitions in the visible wavelength region, and those visible lasers have been reported [1]. Especially, Pr3+-doped lasers are successful so far as one of the most efficient approaches for visible lasing thanks to the development of indium gallium nitride (InGaN) diode lasers.
Highly nonlinear spatial-temporal patterns are inevitable features of lasing in the low-Q (bad) cavities where a photon lifetime, TE, is less than a polarization relaxation time (a lifetime of the optical dipole oscillations), T2, of the individual active centers excited by pumping [1]. A theoretical analysis of the spatial-temporal dynamics of the field and its spectral and correlation features in...
The possibility of using light bullets (LBs), i.e. pulses simultaneously confined in the transverse and the propagation directions, has attracted a lot of interest in the last twenty years, both for fundamental and practical reasons.
Raman fiber lasers (RFLs) are treated as perspective laser sources in spectral bands which are not available from rare-earth (RE) doped fiber lasers. Raman lasing can be easily obtained from 1.1 to 2 μm in single-mode fibers that are core-pumped by RE-doped fiber lasers generating single transverse mode. However, the RFL generation below 1, Mm is difficult because of a lack of suitable high-power...
Already several years ago [3], it was suggested that a laser with optical injection can respond to external perturbations by emitting spikes if the perturbation overcomes a certain threshold, all the spikes being identical to each other, in complete analogy with the behaviour of the simple theta-model neuron [1]. The underlying explanation of this phenomenon lies in the isomorphism between a model...
Pulsed operation characteristics of a high-power 1550 nm tapered distributed Bragg Reflector (DBR) laser diode are described. The development targets applications such as LIDAR and range finding, which require eye-safe, coherent light sources with a high peak-power. In particular, we employ a regrowth-free technique and AlGaInAs/InP gain structure, and demonstrate a peak power of about 1.6 W (drive-current...
GaAs diode laser-based hybrid micro-integration technology meets the demand for precision spectroscopy applications in space for compact, robust, and energy-efficient laser modules. It supports applications at wavelengths ranging from 630 nm to 1200 nm and is already used for quantum optics experiments in space [1].
Application of active disks reduces thermally induced optical effects in powerful solid-state lasers significantly [1]. The next step to improve the quality of output laser emission together with increasing of the output power may be done while using multi beam pumping and degenerate laser cavity configuration [2]. The resonator should be designed to cover in series of all the pumped areas in the...
Microchip resonator based on Nd:YVO4 with intracavity Er-Glass crystal for frequency stabilization of 1064 nm radiation is presented. Auxiliary 1.55μm beam is absorbed in Er-Glass what leads to resonator optical path-length changes by photothermal effect.
For obtaining a single frequency Q-switched laser output injecting a continuous wave single frequency master laser into a Q-switched laser is a commonly used technique [1]. For a stabilized injection seeding a Fast Fourier Transform (FFT) based single heterodyne beat signal technique will be presented.
We report the successfully demonstration of a wavelength tunable passive Q-switched Alexandrite laser with semiconductor saturable absorber mirror (SESAM) and using a red diode (AlGaInP) pump laser at 635 nm. This system allows the potential for low-cost, compact wavelength-tunable short pulse sources, compared to active Q-switch pulsing methods [1, 2].
Femtosecond 1 μm lasers are widely used in numerous scientific and industrial applications [1, 2]. Such oscillators are intensively developed and ultrafast sub-100 fs operation has been already demonstrated in several ytterbium-doped active media. One of the most interesting among them and relatively shortly investigated is Yb:CaF2. This is a simple cubic crystal, with very broadband emission spectrum...
In recent years, the development of compact all solid-state lasers has attracted the scientific community because of their vast scientific and technological applications. In particular, ytterbium (Yb3+) laser sources have been developed with a great number of hosts, due to the promise of the Yb3+ ion related to the very simple energy level structure and absence of higher energy levels, as well as...
Lasers emitting around 2 μm (eye-safe spectral range) are of practical importance for remote sensing, spectroscopy and medicine. Such emission is typically achieved from Tm3+ (3F4 →3H6 transition) and Ho3+ ions (5I7 → 5I8 transition). The search for appropriate saturable absorbers (SAs) for passive Q-switching (PQS) of ∼2 μm lasers is still ongoing. While “slow” SAs, e.g. Cr2+:ZnS, are well-established,...
Kerr optical frequency combs in high-Q microresonators [1] are attracting growing interest [23], especially after mode-locking via dissipative Kerr solitons (DKS) has been demonstrated on a variety of platforms [3, 4]. Such combs are a promising source for compact applications due to its potential advantages of low power consumption and possibility of chip integration. A traditional approach to obtaining...
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