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In forthcoming quantum networks various quantum systems might be involved to accomplish individual tasks, including storage of quantum states, quantum logic operations, error correction, or entanglement distillation. An interface between a single photon emitter and a potential photon storage could provide one fundamental building block of such a hybrid quantum system.
Implementation of a quantum network with single atoms as quantum nodes and single photons as channels between the nodes requires their interfacing in receiver mode, whereby the photonic qubit is mapped onto the internal degrees of freedom of the atom [1]. Combining such a receiver interface with a source of entangled photon pairs enables the distribution of entanglement between network nodes. We implemented...
It was shown that the spectral width of a nominally continuous wave Raman fiber laser (RFL) output becomes narrower after propagation in normal dispersion (β2>0) fiber [1]. This feature, attributed to Inverse Four-Wave Mixing (IFWM), was especially pronounced when the RFL output had a double-peak spectral shape caused by efficient FWM inside the cavity [2]. This spectrum was transformed into a...
Since the free-electron laser FLASH at DESY in Hamburg, Germany [1] lases in Self-Amplified Spontaneous Emission (SASE) mode each pulse is “unique” and has different pulse energy, XUV spectrum and pulse duration. Due to very small fluctuations in the acceleration, the arrival time of the XUV pulses jitters within several tens of femtoseconds. A Terahertz (THz) field driven streak camera [2,3] has...
Photoacoustic microscopy (PAM) is a promising imaging modality that combines optical and ultrasound imaging. It combines the advantages of high ultrasonic spatial resolution and high optical contrast. When a short laser pulse illuminates the tissue, absorbed light leads to an acoustic emission via thermoelastic expansion [1]. The laser system needs to generate short enough pulses, i.e., several nanoseconds,...
We report the generation of tuneable THz radiation (0.75–3 THz) through second order nonlinear effects in the excitation of excitons in GaAs/AlAs multi-quantum wells (MQWs), using readily available continuous wave (CW) laser diodes at room temperature. A MQW GaAs/AlAs sample was designed to have excitonic resonances at a wavelength accessible by commercially available lasers (850nm, 260mW), and have...
Thin metal wires are known to be a low loss and very low dispersion terahertz (THz) waveguide [1]. Recently, generation of a strong THz surface wave was demonstrated by irradiating a wire surface with a ultrahigh intensity femtosecond laser [2]. Such THz light sources driven by femtosecond laser induced plasma are expected to have a high potential as a power scalable source. However, the characteristics...
Intense, ultra-broadband terahertz (THz) pulses can drive major advances in ultrafast dynamics, nonlinear THz optics, and bio-material imaging [1,2]. Single and two-color filamentation of ultrashort laser pulses in gases have been extensively used for the generation of such pulses [3,4]. However, filament formation in gases is hindered by the need of high laser pulse energies, motivating the exploration...
There is a growing interest in the use of metal halide perovskites with different compositions as highly efficient light emitters among the whole visible spectral region [1]. Several groups have observed amplified spontaneous (ASE) emission in thin perovskite films. The gain and threshold values for ASE are very promising, motivating the current effort to develop practical devices that lase.
The peculiar coupling of the spin and the valley degrees of freedom in Transition-Metal Dichalcogenides (TMDs) makes this class of materials very interesting for quantum information and possible valleytronics based devices [1]. In the last year the valley depolarization dynamics in TMDs has been object of an intense study [2, 3, 4, 5].
The transition cross sections on the pump and laser wavelength of rare-earth-doped materials are of crucial importance for their performance as amplifiers and lasers and for the understanding of their performance in a rate-equation model. Since typically part of the absorbed pump power is converted to heat, the temperature of the host material increases with increasing pumping. This implies a temperature-dependent...
In a DBR microcavity with quantum wells embedded, strong coupling between excitons inside the quantum wells with the microcavity photons results in a new particle called exciton polariton. These bosonic particles are partly light and partly matter, thus they can be seen as an effective nonlinearity for light. Because of their bosonic lightweight nature, stimulated scattering into a certain state occurs...
We present a numerical study of the nonlinear dynamics of a population of coupled semiconductor lasers with saturable absorber operating in the excitable regime [1] and described by a set of coupled Yamada models [2]. In particular we have investigated the self-organized synchronization process taking place spontaneously among the lasers, showing significant correlations between the spike-like pulses...
Mid-infrared coherent sources at 3–4 μm have a wide variety of applications that include, but are not limited to gas sensing, material processing and production control. The MgO-doped periodically poled lithium niobate (MgO:PPLN) crystal is a well-known nonlinear element for quasi-phase-matched optical parametric oscillators (OPOs) typically pumped by 1-μm laser radiation [1]. However, strong multi-phonon...
Label-free optical microscopy plays an important role in biological research. Coherent Raman microscopy combines three-dimensional resolution and fast image acquisition with molecular selectivity based on the vibrational spectrum of the sample. During the last years stimulated Raman scattering (SRS) microscopy has become an important technique in this framework since it does not display an electronic...
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...
Fiber and bulk lasers form two distinct classes of solid-state laser, both of which have achieved tremendous success in various arenas, but they are not without their limitations. The long, thin geometry of a fiber allows excellent heat dissipation, which combined with a waveguiding structure provides stronger resilience to thermally-induced mode distortions than in bulk lasers, allowing diffraction-limited...
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.
Nonlinear optical frequency conversion in plasmonics has attracted immense research attention recently. Through various device geometries, harmonic generations of various orders have been reported. However, in these demonstrations, the near-field effect utilized has been limited to localized surface plasmons. It was not until last year that nonlinear frequency conversion utilizing propagating surface...
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