We have proposed a theoretical model to study bistable switching between two optical signals using a vertical cavity semiconductor saturable absorber (VCSSA) operating in reflection mode. The model is based on the carrier rate equation, which predicts cross-absorption phenomena within the absorber region. Simulations are carried out to investigate the effect of various cavity parameters on swit...

We observe a saturable change in the refractive index induced by two-photon absorption in a photochromic polymer, while the erasable nature of the polymer is maintained. As a result, the support region of spatial frequencies of the recorded data bits caused by the refractive index change in the polymer is enlarged. This feature leads to the significant enhancement of the signal level in a refle...

Since the first report of single-layer graphene a few years ago, this material has already proven to possess a great number of interesting properties. One of these properties is its non-linear optical behavior, namely its wavelength-independent saturation of optical absorption. This saturable absorption can be utilized to induce self-amplitude modulation in a laser cavity, thus mode-locking las...

A soluble graphite oxide (GO) axially substituted gallium phthalocyanine (PcGa) hybrid material (GO-PcGa) was for the first time synthesized by the reaction of tBu(4)PcGaCl with GO in anhydrous DMSO at 110 °C in the presence of K(2)CO(3). The formation of a Ga-O bond between PcGa and GO has been confirmed by x-ray photoelectron spectroscopy. In contrast to GO, the D and G bands of GO-PcGa in th...

Optical metasurfaces are endowed with unparallel flexibility to manipulate the light field a subwavelength spatial resolution. Coupling materials strong optical nonlinearity may allow ultrafast spatiotemporal modulation. However, most demonstrated thus far linear devices. Here, we experimentally demonstrate simultaneous laser mode control using single-layer plasmonic metasurface strongly couple...

The study presents a novel demonstration of a passively mode-locked erbium-doped fiber laser (EDFL) that is based on a silicon carbide (SixC1-x) saturable absorber. When the C/Si composition ratio is increased to 1.83, the SixC1-x film transforms from two-photon absorption to nonlinear saturable absorption, and the corresponding value reaches -3.9 × 10(-6) cm/W. The Si-rich SixC1-x film cannot ...

The purpose of the study was to elucidate mechanisms of metformin absorptive transport to explain the dose-dependent absorption observed in humans. Apical (AP) and basolateral (BL) uptake and efflux as well as AP to BL (absorptive) transport across Caco-2 cell monolayers were evaluated over a range of concentrations. Transport was concentration-dependent and consisted of saturable and nonsatura...

The silicon optical modulator is considered to be the workhorse of a revolution in communications. In recent years, the capabilities of externally driven active silicon optical modulators have dramatically improved. Self-driven passive modulators, especially passive silicon modulators, possess advantages in compactness, integration, low-cost, etc. Constrained by a large indirect band-gap and se...

Single-walled carbon nanotube encapsulated in boron nitrite (SWCNT@BNNT) is a novel nanomaterial with one-dimensional van der Waals (1D-vdW) heterostructure. In this paper, we demonstrated that the SWCNT@BNNT has an enhanced optical power tolerance compared to of pristine SWCNT while exhibiting saturable absorption properties. Under intensity 13kW/cm2, lifetime found be 2,270 times longer than ...