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Ultrafast terahertz (THz) transients are of great interest for linear and nonlinear THz spectroscopy and compact particle acceleration. Tilted-pulse-front (TPF) [1] THz generation in lithium niobate (LN) has become ubiquitous due to its compatibility with easily accessible high-power 800 nm/1 µm laser technology. However, the use of diffraction grating (DG) based TPFs (DG-TPFs) present formidable...
When a metal nanostructure is locally photoexcited at a resonant wavelength, a plasmonic wave packet is generated and propagates on the surface of the nanostructure. The wave packet dynamics is closely related to plasmon mode characteristics of the material, and is regarded as one of major origins of the unique optical characteristics of metal nanostructured materials. Spatial scales of plasmon resonances...
We measure the opto-electronic properties of femtosecond-laser-ablated GaAs and demonstrate its utility towards THz devices. In particular, we show that laser-ablated THz antennas are 65% more efficient than non-ablated antennas at high powers. Our results demonstrate the possibility of using femtosecond-laser-ablation as a cost-effective technique to engineer material properties for THz devices.
We design and investigate a monolithically integrated wavelength converter based on a tunable V-cavity laser with a Mach-Zehnder interferometer with independent phase control. A 6.25 Gb/s non-return-to-zero conversion has been modeled using time-domain traveling-wave method.
Hyperbolic metasurfaces (HMS) combine the potential for chip-scale integration of optical metasurfaces with the properties of hyperbolic dispersion. In the ideal, lossless effective medium limit, HMS have an unbound optical density of states (DOS). The unbound DOS enables infinite mode densities in waveguides and cavities, and, in principal, an infinitely confined modal energy. The finite periodicity...
Semiconductor microwires have attracted much current attention due to their excellent geometric uniformities, inherent optical gain, relatively high refractive index, making them potential candidates for microscale electronic and optoelectronic building blocks, especially as the next frontier in miniaturization of semiconductor lasers. Recently, organic-lead halide perovskite semiconductors (CH3NH...
Modulational instability is a phenomenon that reveals itself as the exponential growth of weak perturbations in the presence of an intense pump beam propagating in a nonlinear medium. It plays a key role in such nonlinear optical processes as supercontinuum generation, light filamentation, rogue waves, and ring (or necklace) beam formation. To date, a majority of studies of these phenomena have focused...
We will report on our latest experimental result on atom-light hybrid interferometer. We demonstrated a new type of hybrid atom-light interferometer [1] with two atomic Raman amplification processes (RA1 and RA2) replacing the beam splitting elements in a traditional interferometer. Different with conventional optical interferometer, the first beam splitter process in atom-light hybrid interferometer...
In this paper the authors demonstrate a model of a multicarrier light source for wavelength division multiplexed transmission systems, where two dual-pump fiber optical parametric amplifiers are used to increase the number of initial carriers three times. The optical radiation of the 16 initial carriers is combined and afterwards divided among the two parametric amplifiers, which are placed in parallel...
This paper presents the evaluation of gain, Amplified Spontaneous Emission (ASE) noise figure depending on the different Erbium Doped Fiber Amplifier (EDFA) and input signal parameters which are simulated in 10 Gbit/s single channel fiber optic transmission system with 1550nm wavelength. The obtained results show that the EDFA amplification simultaneously depends on various parameters such as input...
The main goal of this paper is to investigate and compare the performance of an erbium-doped fiber amplifier and a lumped Raman amplifier when they are used as preamplifiers. For this purpose a simulation model of a 8 channel 10 Gbps dense wavelength division multiplexed transmission system with non-return-to-zero intensity on-off keying modulation, 100 GHz channel spacing and a discrete preamplifier...
The main goal of this paper is to investigate and compare the performance of an in-line distributed Raman amplifiers in cases of co and counter propagating pumping radiation in respect to the propagation direction of the amplified signal. The performance analysis is based on the results obtained in a 16 channel 10 Gbps dense wavelength division multiplexed optical transmission system with 50 GHz channel...
Graphene plasmonics provides a unique and robust platform for nonlinear optics. Defining features for graphene nonlinear plasmonics include the extreme optical confinement, giant Kerr nonlinear conductivity and configurable Fermi-level. With the recent theoretical examination of graphene's real and imaginary nonlinear conductivity by Cheng, Vermeulan and Sipe, we are able to study the full picture...
Optical metasurfaces have the potential of leading to compact integrated optical nano-devices for beam shaping, direction, polarization and phase control of light, and have been used for lensing and holography [1]. Metasurfaces can also be used for nonlinear optics [2]. A promising application of this is the efficient generation of second and third harmonic signals [3]: the small thickness of metasurfaces...
In this paper, we present an environmentally stable all-polarization-maintaining Erbium-doped Q-switched fiber laser based on WSe2-PVA as a saturable absorber. WSe2-PVA film is synthesized by liquid phase exfoliation. We let the fiber laser continue to work twelve hours, and we keep a record of the output power, optical spectrum, and frequency spectrum every thirty minutes. The results shows the stability...
In this paper, we report a MoSe2-PVA based saturable absorber and related experiment results of polarization maintaining Q-switched fiber laser. MoSe2-PVA film is synthesized by liquid phase exfoliation method and its saturable absorption is measured via a nonlinear transmission experiment. The result shows that MoSe2-PVA saturable absorber has a modulation depth of 9.8%, which demonstrates its potential...
In present research, Aeff parameter measurements for ytterbium (Yb3+) and erbium (Er3+) doped optical fibers were performed experimentally by the usage of transverse shift measurement method. All the measurements were done at two different wavelengths (1310nm and 1550nm accordingly) at various power levels with an aim to evaluate how effective area depends on those parameters. With the increase of...
Solution-processed lead halide perovskites have shown very bright future in both solar cells and microlasers. Very recently, the nonlinearity of perovskites started to attract considerable research attention. However, the perovskite nonlinear devices are still absent. Here we demonstrate the two-photon pumped nanolasers from perovskite nanowires. The CH3NH3PbBr3 perovskite nanowires were synthesized...
The technology of different special optical fibers fabrication is considerably developing [1]. Fiber with metal electrodes in the cladding is now possible. In some papers, such fibers are applied as electrooptic modulators of light, in others - for fiber poling [2]. Photonic crystal fibers with electrodes made possible polarization switching [3] and plasmonic resonance temperature sensing [4]. We...
Terahertz (THz) spectral band, from about 0.1 to 15 THz, is one of the least explored yet most technologically transformative spectral regions. A large number of interesting scientific phenomena are only accessible by THz photons and THz radiation also finds a lot of practical applications. However, for a long time, THz scientific research and technological development is greatly limited due to the...
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