Switching behaviour of a nonlinear Mach-Zehnder interferometer

In the present paper, a detailed investigation on the switching behaviour of a nonlinear Mach-Zehnder interferometer (NMZI) has been carried out using beam propagation method (BPM). A thorough investigation on input vs. output characteristic has been carried out by varying different parameters like length of the arms, refractive index of the linear/nonlinear arm, wavelength of the input beams and nonlinear coefficient of the material of the nonlinear arm. The input vs. output characteristic has also been investigated by shifting the balance point of the NMZI. The present paper provides a physically intuitive understanding of the effect of change in different parameters of the NMZI on its switching behaviour.     

Coupled spatial-soliton pairs in saturable nonlinear media

We present a simple and straightforward approach to investigate coupled spatial-soliton pairs of two copropagating mutually incoherent (i.e., both beams are fully spatially and temporally coherent, but are incoherent with respect to one another) light beams in saturable nonlinear media. The approach provides a deeper understanding of coupled spatial-soliton pairs and reveals many interesting features, including the entire existence curve of such solitons.     

Reactions of Podophyllotoxin with DDQ

Introduction 2, 3-Dichloro-5, 6-dicyanobenzoquinone (DDQ) can react with lignans of the mono- arylidene-butyrolactone1, aryltetralin2, dibenzylbutane3 and aryltetralin-butyrolactone4,5 series. We have studied the reactions of this reagent with podophyllotoxin 1, which is a well-known natural product on account of its long history of use in folk medicine and the biological activity of its many derivatives6. In particular, derivatives of 4-demethyl epipodophyllotoxin are used in cancer chemo…     

All-optical circulator based on cross phase modulation in a nonlinear Mach-Zehnder interferometer

We show that by exploiting unequal magnitude of cross phase modulation (XPM) in co-propagating and counter-propagating beams, an all-optical circulator (AOC) using a nonlinear Mach-Zehnder Interferometer (MZI) could be constructed. The proposed circulator is novel, simple and polarization independent.     

Optimally stabilized beam pairs

In this paper, evolution of two co-axially co-propagating beams with the propagation distance in a Kerr type nonlinear medium has been analyzed for all possible physical parameters and situations. For the first time, the paper analyzes useful “optimally stabilized” (minimum width oscillations of beams with distance of propagation) pairing of bright-bright, bright-dark, dark-dark beams of same/different wavelengths and of same/different widths using coupled nonlinear Schrödinger equation (NLSE) that has been solved using split-step Fourier method. Soliton pairs of two unequal beam widths are known to be impossible, however, it is shown that “optimally stabilized” pairing is possible in such cases. Existence surfaces for optimally stabilized pairing have also been revealed for different interaction coefficient of the coupled beams.