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The helium-neon (HeNe) laser with its characteristic wavelength of 633 nm is one of the most well-known and successful laser systems. Although it was already invented in 1961 [1], the HeNe laser is still the basis for many optical metrology techniques and has found many applications in the fields of manufacturing, medicine and quantum optics. However, the range of implementations for emission at this...
Microwave photonics is the study of the interaction between microwave and optical waves and their applications. One area of significant interest is the photonic generation of a microwave signal. Several techniques have been developed to generate such photonic microwave sources [1]. In particular, one popular method for generating photonic microwave uses Period-one (P1) oscillations from optically...
Localized structures often called cavity solitons in optics have been observed in various systems of nonlinear science such as chemistry, physics, plant ecology and optics [1]. Scalar cavity solitons have been reported in the broad area [2] and in medium size vertical cavity surface emitting lasers [3]. The polarization degree of freedom was not considered in these works.
Mechanically interlocked molecules represent chemical architectures whose composing elements are linked because of their topology instead of covalent bonds [1]. Among them, the catenanes are analogous to an ensemble of interlaced rings, globally locked yet locally independent. We disclose in this work the equivalent of such exotic molecules in the realm of nonlinear Photonics. They appear as interlocked...
Semiconductor lasers operating in the UV-C band (100–280 nm) are important for a broad range of applications including surface treatment, bio-agent detection and the production of microelectronics and integrated circuits. To date, however, it has remained challenging to achieve electrically injected AlGaN quantum well lasers operating in these wavelengths, due to the presence of large densities of...
Three years after the first realization [1] of the vertical external-cavity surface-emitting laser (VECSEL), passive mode locking by inserting a semiconductor saturable absorber mirror (SESAM) into the cavity was presented [2]. Besides the advantageous properties in continuous wave operation such as a near-diffraction limited beam profile and the possibility of bandgap engineering, SESAM mode-locked...
Vertical-cavity surface-emitting lasers (VCSELs) are widely used in short-range optical data transmission and optical sensing. Tailored heating and infrared illumination with large two-dimensional parallel-driven VCSEL arrays are gaining more and more attention. In the latter fields as well as in high-speed datacom the laser performance is limited by internal heating at high operating currents or...
Microchips are more and more complex and designed in thick 3 dimensional packages. In order to access and characterize by electron microscopy (SEM and TEM) any detected defect responsible for malfunction of the device, a large quantity of matter needs to be removed without damaging the surrounded area. The available techniques, such as plasma Focused Ion Beam (FIB), allow achieving high quality surfaces...
In semiconductor-coupled micro and nano-cavities, the combination between tight light confinement and high optical nonlinearities open up new routes for the study of light-matter interaction in non-equilibrium driven dissipative systems. Even at the semiclassical level, coupled cavities may display a wide range of rich nonlinear dynamical phenomena such as instabilities and bifurcations [1]. Mode...
Current confinement in vertical-cavity surface-emitting lasers (VCSELs) is nowadays realized most commonly with buried AlxOy oxide apertures very close to the active region [1]. A novel oxide-free and regrowth-free approach uses the generated spontaneous light in the laser resonator in association with an epitaxially integrated phototransistor (PT) for an optical definition of the current path through...
The expansion of cellular networks over the past decades has gone through an astonishing evolution. Due to centralized network functions, splitting of the generation/processing of RF signal in base band units (BBUs) and the baseband-RF conversion in remote radio heads (RRHs) has become inevitable. To systematically overcome the bandwidth and latency issues, a cost-efficient WDM-PON capable of linking...
Spin-polarized vertical-cavity surface-emitting lasers (spin-VCSELs) offer the opportunity to generate high frequency polarization modulation dynamics, potentially enabling ultrafast optical communications. We use pulsed circular polarized optical pumping, leading to a transient spin imbalance in the carrier-spin-photon system via the optical selection rules. This results in an oscillation in the...
Interband cascade lasers (ICLs) [1, 2] combine two concepts for semiconductor lasers, in particular the long carrier lifetime of photodiodes together with the voltage-efficient cascading of the quantum cascade laser. The low threshold power makes them very attractive for mobile systems used for spectroscopy, process control or medical applications. To date no suitable overgrowth process exists for...
For silicon photonics, specifically chip-level optical interconnects, an ultrahigh-speed low-energy-consuming laser that can be integrated onto a silicon (Si) wafer is an ideal element. Here, we report on a hybrid Si-on-chip micro-cavity laser structure with a potential of providing such characteristics. As shown in Fig. 1a, the laser structure is a vertical cavity, consisting of a high contrast grating...
Thanks to the recent spintronics advancement, new applications should emerge, like fast communications with spin coding. For instance, data transmission by coding the polarization state of a spin-injected laser source [1] is enabling new modulation formats and wide frequency bandwidths. In comparison to semiconductor edge-emitting lasers where only one polarization is guided, vertical cavity surface...
Laser technology is finding applications in areas such as high resolution spectroscopy, radar-lidar, velocimetry, and more recently in the THz domain such as imaging or spectroscopy, where highly coherent tunable high power light sources are required. The Vertical External Cavity Surface Emitting Laser (VECSEL) technology [1] has been identified for years as a good candidate to reach high power high...
The emergence of antibiotic resistance of bacteria to many major antibiotics has made the study of the growth of bacterial pathogens very important in the discovery and development of novel drugs [1, 2]. Metabolic activities in bacterial cultures lead to concomitant emission of a variety of gases. Accurate measurement of the mole fractions of these gases is an indirect but reliable measure of bacterial...
It has been shown earlier, that the injection locked semiconductor lasers enable effective amplitude noise suppression [1] and makes possible an extra level of signal multiplexing-orthogonal modulation [2], where DPSK and ASK NRZ channels propagate at the same wavelength [3]. In our work we use an injection-locked 1550 nm VCSEL as a slave laser providing separation of amplitude and phase modulations,...
We report on the transmission of 108 Gbit/s, 99 Gbit/s, and 90 Gbit/s PAM-8 signal over 25 m, 75 m, and 125 m OM3 multi-mode fiber (MMF), respectively. These bit rates are achieved with an 850 nm GaAs multi-mode (MM) vertical cavity surface emitting laser (VCSEL) transmitter and a GaAs PIN photodiode (PD).
Three-dimensional solitons are highly sought after objects in nonlinear science. In nonlinear photonics they correspond to light bullets, but their experimental observation as long-term stable structures remains elusive in spite of impressive advances [1]. Broad-area vertical-cavity surface-emitting lasers (VCSELs) combine a large Fresnel number with a high nonlinearity and fast time scales. Stationary...
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