Sandeep Vyas

Bio: Sandeep Vyas is an academic researcher from Jaipur Engineering College. The author has contributed to research in topics: Supercontinuum & Photonic-crystal fiber. The author has an hindex of 4, co-authored 14 publications receiving 65 citations. Previous affiliations of Sandeep Vyas include Vivekananda Institute of Technology.

Chalcogenide photonic crystal fiber for ultraflat mid-infrared supercontinuum generation

Abstract: In this Letter, we numerically simulate the generation of a 1–15 μm mid-infrared supercontinuum (SC) from a highly nonlinear Ge11.5As24Se64.5-based photonic crystal fiber (PCF). This ultra-broadband SC is achieved in a 100 mm long PCF pumped using 85 fs laser pulses operated at 3.1 μm and a peak pulse power of 3 kW. The proposed design offers a flat dispersion profile with two zero dispersion wavelengths. This broad and flat dispersion profile of the Ge11.5As24Se64.5 PCF, combined with the high nonlinearity (2474 W−1 km−1), generates an ultra-broadband SC.

Mid-infrared supercontinuum generation in Ge 11.5 As 24 Se 64.5 based chalcogenide photonic crystal fiber

Abstract: In this paper, we have numerically investigated a Ge 11.5 As 24 Se 64.5 based chalcogenide photonic crystal fiber and simulated 1–10 μm mid-infrared supercontinuum generation. This mid-infrared broadband supercontinuum is achieved for 100 mm long photonic crystal fiber pumped with 85 femtosecond laser pulses operated at 3.1 μm and peak power pulse is 3 kW. A broad and flat dispersion profile with two zero dispersion wavelengths of Ge 11.5 As 24 Se 64.5 photonic crystal fiber combined with the high nonlinearity and generate ultra flat broadband supercontinuum.

Broadband supercontinuum generation and Raman response in Ge11.5As24Se64.5 based chalcogenide photonic crystal fiber

Abstract: We numerically demonstrated that the generation of 1.4–10 µm mid-infrared supercontinuum from highly nonlinear Ge11.5As24Se64.5 based photonic crystal fiber chalcogenide glass. This ultra-broadband supercontinuum achieved for 150 mm long photonic crystal fiber pumped with 85 femto-second laser pulses operated at 3.1 µm and peak power pulse is 5 kW. A broad and flat dispersion profile of Ge11.5As24Se64.5 PCF associated with the extreme nonlinearity and generate hyper broadband supercontinuum. Raman gain of Ge11.5As24Se64.5 glass is four times higher to fused silica and As2Se3 glass and Raman frequency shift for the Ge11.5As24Se64.5 glass is ≈ 7.1 THz.

Investigation of As2S3-borosilicate chalcogenide glass-based dispersion-engineered photonic crystal fibre for broadband supercontinuum generation in the mid-IR region

Abstract: In the paper, a spirally filled solid core chalcogenide-based photonic crystal fibre is proposed, which is engineered to obtain a flattened broad anomalous dispersion profile. The spectrum spanning...

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Supercontinuum generation, photonic crystal fiber

Abstract: A topical review of numerical and experimental studies of supercontinuum generation in photonic crystal fiber is presented over the full range of experimentally reported parameters, from the femtosecond to the continuous-wave regime. Results from numerical simulations are used to discuss the temporal and spectral characteristics of the supercontinuum, and to interpret the physics of the underlying spectral broadening processes. Particular attention is given to the case of supercontinuum generation seeded by femtosecond pulses in the anomalous group velocity dispersion regime of photonic crystal fiber, where the processes of soliton fission, stimulated Raman scattering, and dispersive wave generation are reviewed in detail. The corresponding intensity and phase stability properties of the supercontinuum spectra generated under different conditions are also discussed.

Ultraflat, broadband, and highly coherent supercontinuum generation in all-solid microstructured optical fibers with all-normal dispersion

Abstract: High flatness, wide bandwidth, and high-coherence properties of supercontinuum (SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, since special dispersion profiles are required, especially when pump pulses with duration over 100 fs are employed. We propose an all-solid microstructured fiber composed only of hexagonal glass elements. The optimized fiber possesses an ultraflat all-normal dispersion profile, covering a wide wavelength interval of approximately 1.55 μm. An SC spectrum spanning from approximately 1030 to 2030 nm (corresponding to nearly one octave) with flatness <3 dB is numerically generated in the fiber with 200 fs pump pulses at 1.55 μm. The results indicate that the broadband ultraflat SC sources can be all-fiber and miniaturized due to commercially achievable 200-fs fiber lasers. Moreover, the SC pulses feature high coherence and a single pulse in the time domain, which can be compressed to 13.9-fs pulses with high quality even for simple linear chirp compensation. The Fourier-limited pulse duration of the spectrum is 3.19 fs, corresponding to only 0.62 optical cycles.