Second harmonic generation (SHG) is applied for the first time to study the surfaces of clay particles. An SHG signal was detected from an aqueous suspension of disk-shaped montmorillonite clay particles of 0.5 μm diameter and 0.01 μm thickness. The origin of the SHG signal is the polarization of water molecules by surface charges located in the edge region of the clay particles. On addition of...

Micro finance has garnered significant worldwide attention as being a successful tool to meet substantial demand for financial services by low-income. India occupies a significant place and a niche in global micro finance through promotion of the Self Help Groups and the home grown SHG-Bank Linkage Programme model. It is observed that different stakeholders have promoted SHGs with different exp...

The emergence of second-harmonic generation (SHG) is a pivotal issue to the development of nano-optical devices and interfaces. Here, we perform a classical analysis of the SHG dynamics with the aim of determining critical values of the electric field. The signals of the SHG process are nonlinear, so it seems reasonable that chaos theory can be a suitable tool to analyze their dynamics. For thi...

Multiphoton microscopy relies on nonlinear light-matter interactions to provide contrast and optical sectioning capability for high-resolution imaging. Most multiphoton microscopy studies in biological systems have relied on two-photon excited fluorescence (TPEF) to produce images. With increasing applications of multiphoton microscopy to thick-tissue "intravital" imaging, second-harmonic gener...

We performed multiphoton fluorescence (MF) and second-harmonic generation (SHG) imaging on human basal cell carcinoma samples. In the dermis, basal cell carcinomas can be identified by masses of autofluorescent cells with relatively large nuclei and marked peripheral palisading. In the normal dermis, SHG from dermal collagen contributes largely to the multiphoton signal. However, within the can...

Second-harmonic generation imaging (SHG) captures triple helical collagen molecules near tissue surfaces. Biomedical research routinely utilizes various imaging software packages to quantify SHG signals for collagen content and distribution estimates in modern tissue samples including bone. For the first time using SHG, samples of modern, medieval, and ice age bones were imaged to test the appl...

This work investigates the structural and nonlinear optical properties of a D-A type 1-[4-({(E)-[4-(methylsulfanyl)phenyl]methylidene}amino)phenyl]ethanone, MMP in which charge transfer occurs from -SCH3 donor to -COCH3 acceptor group through methylidene backbone; and some of its modeled analogues using quantum chemical calculations with pure BLYP and hybrid B3LYP correlation with high basis se...

1,3-Dibromo-2,4,6-trinitrobenzene (DBTNB), a two-dimensional charge transfer hyperpolarisable chromophore, crystallizes in the non-centrosymmetric space group C2 in perfect polar order leading to an intense powder SHG signal at 1.06 microns.

The transparency and mechanical strength of the cornea are related to the highly organized three-dimensional distribution of collagen fibrils. It is of great interest to develop specific and contrasted in vivo imaging tools to probe these collagenous structures, which is not available yet. Second Harmonic Generation (SHG) microscopy is a unique tool to reveal fibrillar collagen within unstained...

We have previously developed a new way for nonscanning second-harmonic generation (SHG) microscopy [Opt. Lett. 34, 2450 (2009)]. Based on digital holography, this technique captures, in single-shot hologram acquisition, both the amplitude and the phase of a coherent SHG radiation, which makes possible second harmonic phase microscopy. In this work, we present holographic SHG phase microscopy of...