Author
Anirban Dhar
Other affiliations: University of Southampton, Academy of Scientific and Innovative Research, Indian Institute of Technology Kharagpur ...read more
Bio: Anirban Dhar is an academic researcher from Central Glass and Ceramic Research Institute. The author has contributed to research in topics: Optical fiber & Fiber laser. The author has an hindex of 18, co-authored 166 publications receiving 1755 citations. Previous affiliations of Anirban Dhar include University of Southampton & Academy of Scientific and Innovative Research.
Topics: Optical fiber, Fiber laser, Fiber, Erbium, Laser
Papers published on a yearly basis
Papers
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TL;DR: In this paper, a reusable nano-size gold catalyst supported on U3O8, MgO, Al2O3 or ZrO2 was used to oxidize benzyl alcohol to benzaldehyde with high yield, with a little formation of benzylbenzoate.
192 citations
TL;DR: The total demonstrated net capacity, taking into account 20% of FEC-overhead and 7.5% additional overhead (Ethernet and training sequences), is 57.6 Tb/s, corresponding to a spectral efficiency of 12 bits/s/Hz.
Abstract: Transmission of a 73.7 Tb/s (96x3x256-Gb/s) DP-16QAM mode-division-multiplexed signal over 119km of few-mode fiber transmission line incorporating an inline multi mode EDFA and a phase plate based mode (de-)multiplexer is demonstrated. Data-aided 6x6 MIMO digital signal processing was used to demodulate the signal. The total demonstrated net capacity, taking into account 20% of FEC-overhead and 7.5% additional overhead (Ethernet and training sequences), is 57.6 Tb/s, corresponding to a spectral efficiency of 12 bits/s/Hz.
151 citations
16 Sep 2012
TL;DR: In this article, a 73.7 Tb/s (96×3×256Gb/s) DP-16QAM mode-division-multiplexed signal over 119km of few-mode fiber with inline multi-mode EDFA, using 6x6 MIMO digital signal processing.
Abstract: We show transmission of a 73.7 Tb/s (96×3×256-Gb/s) DP-16QAM mode-division-multiplexed signal over 119km of few-mode fiber with inline multi-mode EDFA, using 6x6 MIMO digital signal processing. The total demonstrated net capacity is 57.6 Tb/s (SE 12 bits/s/Hz).
133 citations
TL;DR: The first demonstration of a multimode (two mode-group) erbium-doped fiber amplifier for Space Division Multiplexed (SDM) applications is presented and differential modal gains can be controlled and reduced both by fiber design and control of the pump field distribution.
Abstract: We present the first demonstration of a multimode (two modegroup) erbium-doped fiber amplifier for Space Division Multiplexed (SDM) applications and demonstrate various design and performance features of such devices. In particular we experimentally demonstrate that differential modal gains can be controlled and reduced both by fiber design and control of the pump field distribution. Using a suitably designed fiber we demonstrate simultaneous modal gains of ~20dB for different pair-wise combinations of spatial and polarization modes in an EDFA supporting amplification of 6 distinct modes.
124 citations
TL;DR: Using a comprehensive numerical model of thulium doped fiber, efficient lasing can be expected even for silica based fiber for specific ranges of the fiber and laser cavity parameters, especially when 3H4 lifetime is enhanced.
Abstract: A compact upconversion fiber laser operating around 810 nm is proposed using thulium-doped silica-based fiber with locally modified thulium environment by high alumina codoping. Using a comprehensive numerical model of thulium doped fiber we investigate performance of the proposed laser. Comparison with two other thulium hosts, fluoride glass and standard silica, is presented. Efficient lasing can be expected even for silica based fiber for specific ranges of the fiber and laser cavity parameters, especially when 3H4 lifetime is enhanced. With moderate pump power of 5 W at wavelength of 1064 nm, the predicted output power of the upconversion laser is about 2 W at 810 nm.
85 citations
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TL;DR: In this paper, the authors summarized the simultaneous transmission of several independent spatial channels of light along optical fibres to expand the data-carrying capacity of optical communications, and showed that the results achieved in both multicore and multimode optical fibers are documented.
Abstract: This Review summarizes the simultaneous transmission of several independent spatial channels of light along optical fibres to expand the data-carrying capacity of optical communications. Recent results achieved in both multicore and multimode optical fibres are documented.
2,629 citations
TL;DR: This paper focuses on SDM for fiber-optic communication using few-mode fibers or multimode fibers, in particular on the critical challenge of mode crosstalk, and presents the prospects for SDM in optical transmission and networking.
Abstract: Space-division multiplexing (SDM) uses multiplicity of space channels to increase capacity for optical communication. It is applicable for optical communication in both free space and guided waves. This paper focuses on SDM for fiber-optic communication using few-mode fibers or multimode fibers, in particular on the critical challenge of mode crosstalk. Multiple-input–multiple-output (MIMO) equalization methods developed for wireless communication can be applied as an electronic method to equalize mode crosstalk. Optical approaches, including differential modal group delay management, strong mode coupling, and multicore fibers, are necessary to bring the computational complexity for MIMO mode crosstalk equalization to practical levels. Progress in passive devices, such as (de)multiplexers, and active devices, such as amplifiers and switches, which are considered straightforward challenges in comparison with mode crosstalk, are reviewed. Finally, we present the prospects for SDM in optical transmission and networking.
621 citations
TL;DR: This critical review covers the recent development of the catalytic properties of gold in the selective oxidation of organic compounds, highlighting the exciting contribution to the art of catalysis by international efforts towards optimised synthesis of products of industrial appeal.
Abstract: This critical review covers the recent development of the catalytic properties of gold in the selective oxidation of organic compounds, highlighting the exciting contribution to the art of catalysis. The unique, outstanding properties of nanometre-scale particles of gold, a biocompatible non-toxic metal, have allowed the development of a new generation of stable and selective catalysts for the conversion of many organic feedstocks to valuable chemicals. A critical discussion of the results of different research groups is presented along with attempts to correlate the catalytic properties with catalyst morphology in non-equivalent series of experiments. Particular emphasis has been given to the international efforts towards optimised synthesis of products of industrial appeal such as propylene oxide, vinyl acetate monomer, cyclohexanol/cyclohexanone, gluconic acid and glyceric acid (168 references).
617 citations
TL;DR: This poster presents a probabilistic procedure to characterize the response of the immune system to x-ray diffraction and three different types of deposits are confirmed to be Na6(CO3), Na4(SO4) and Na2(SO3).
Abstract: the National Natural Science Foundation of China (21073208);the Chinese Academy of Sciences
616 citations
TL;DR: The size and shape effects of catalyst particles on catalytic activity and selectivity of reactions performed at solid-gas or solid-liquid interfaces are discussed with a purpose of establishing correlations of size- and shape-dependent chemical and structural factors of surface of a catalyst with the corresponding catalytic performances toward understanding of catalysis at a molecular level.
Abstract: Heterogeneous catalysis is one of the most important chemical processes of various industries performed on catalyst nanoparticles with different sizes or/and shapes. In the past two decades, the catalytic performances of different catalytic reactions on nanoparticles of metals and oxides with well controlled sizes or shapes have been extensively studied thanks to the spectacular advances in syntheses of nanomaterials of metals and oxides. This review discussed the size and shape effects of catalyst particles on catalytic activity and selectivity of reactions performed at solid–gas or solid–liquid interfaces with a purpose of establishing correlations of size- and shape-dependent chemical and structural factors of surface of a catalyst with the corresponding catalytic performances toward understanding of catalysis at a molecular level.
506 citations