A5000450376- Semiconductor materials and devices
- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Silicon Nanostructures and Photoluminescence
- Semiconductor materials and interfaces
- Nanowire Synthesis and Applications
- Electronic and Structural Properties of Oxides
- Perovskite Materials and Applications
- Ferroelectric and Piezoelectric Materials
- Photonic and Optical Devices
- Quantum Dots Synthesis And Properties
- Semiconductor Quantum Structures and Devices
- ZnO doping and properties
- Advanced Memory and Neural Computing
- Optical Network Technologies
- Organic Light-Emitting Diodes Research
- Semiconductor Lasers and Optical Devices
- Photonic Crystal and Fiber Optics
- Advancements in Semiconductor Devices and Circuit Design
- Thin-Film Transistor Technologies
- Chalcogenide Semiconductor Thin Films
- Ferroelectric and Negative Capacitance Devices
- Advanced Fiber Laser Technologies
- Advanced Photonic Communication Systems
- Magnetic and transport properties of perovskites and related materials
Indian Institute of Technology Kharagpur
2013-2024
Central Glass and Ceramic Research Institute
2018
Arizona State University
2015
Intel (United States)
2015
University of Southampton
2011-2014
Indian Institute of Technology Indore
2011
Indian Institute of Tropical Meteorology
2007-2009
Texas Tech University
2003
Indian Association for the Cultivation of Science
1988-1992
Queen's University
1991-1992
Transmission of a 73.7 Tb/s (96x3x256-Gb/s) DP-16QAM mode-division-multiplexed signal over 119km few-mode fiber transmission line incorporating an inline multi mode EDFA and phase plate based (de-)multiplexer is demonstrated.Data-aided 6x6 MIMO digital processing was used to demodulate the signal.The total demonstrated net capacity, taking into account 20% FEC-overhead 7.5% additional overhead (Ethernet training sequences), 57.6 Tb/s, corresponding spectral efficiency 12 bits/s/Hz.
We present the first demonstration of a multimode (two modegroup) erbium-doped fiber amplifier for Space Division Multiplexed (SDM) applications and demonstrate various design performance features such devices.In particular we experimentally that differential modal gains can be controlled reduced both by control pump field distribution.Using suitably designed simultaneous ~20dB different pair-wise combinations spatial polarization modes in an EDFA supporting amplification 6 distinct modes.
We show transmission of a 73.7 Tb/s (96×3×256-Gb/s) DP-16QAM mode-division-multiplexed signal over 119km few-mode fiber with inline multi-mode EDFA, using 6x6 MIMO digital processing. The total demonstrated net capacity is 57.6 (SE 12 bits/s/Hz).
The fabrication and testing of Teflon AF-coated channels on silicon bonding the same to a similarly coated glass wafer are described. With water or aqueous solutions in such channels, exhibit much better light conduction ability than similar uncoated channels. Although loss is greater extruded AF tubes, throughput far superior described literature consisting [110] planes with 45° sidewalls. Absorbance noise levels under actual flow conditions using an LED source, inexpensive photodiode...
Indium tin oxide (ITO) thin films have been deposited by rf magnetron sputtering on glass substrates at different substrate temperatures. The structural, electrical and optical properties of these investigated to obtain optimum values for resistivity, transmittance surface smoothness. film a temperature 300 °C shows good conductivity, transmittance, crystallinity These ITO were used fabricate organic light emitting diodes (OLEDs). dc current–voltage (I–V) studies ITO/PEDOT:PSS/MEH-PPV/Al...
Multilevel conductance switching in organic memory devices based on AlQ3 and Al/Al2O3 core-shell nanoparticles is demonstrated. The effect of middle Al layer thickness the size device performance are investigated. high-resolution transmission electron micrographs revealed formation nanoparticles. has shown a series states. These states nonvolatile nature can be accessed by applying proper programming voltage above threshold voltage. Field-induced transfer charge carriers between aluminum...
Nickel nanocrystal (Ni-NC)-embedded titanium dioxide films have been deposited for nonvolatile resistive switching memory devices. The polycrystalline behavior of the has observed from X-ray diffraction spectra. Tiny isolated Ni-NCs with an average size 4 nm are 1000 °C, 5-min annealed samples. Stable, bipolar, nonvolatile, and bistable states optimized Ni-NC-embedded devices a low SET RESET voltage 0.8 −0.2 V, respectively. A high resistance ratio (>10 <formula formulatype="inline"...
Metal-oxide-semiconductor capacitors with a trilayer structure consisting of the cap gate oxide, sputtered SiGe layers and thermally grown tunnel oxide were fabricated on p-Si substrates. The structures rapid thermal annealed at 1000 °C in nitrogen atmosphere for different durations. Cross-sectional transmission electron micrographs revealed complete isolation Ge nanocrystals sandwiched longer duration. optical charge storage characteristics studied through photoluminescence spectroscopy...
Unipolar nonvolatile resistive switching memory properties of pulse laser ablated nickel oxide films have been studied. Grazing incidence x-ray diffraction and electron spectra the reveal polycrystalline nature deposited NiO films. Cross-sectional transmission micrograph shows a fairly uniform surface. The rms surface roughnesses oxides studied as function annealing temperature using atomic force microscopy. By applying proper voltage bias compliance, Pt/NiO/Pt structures exhibited unipolar...
CdS nanowires have been grown by a two-cell chemical method using porous alumina template. Field-emission scanning and transmission electron microscopy show the growth of diameters ranging from 100 to 110 nm 50 60 for two different templates. The surface topography template filled with has studied atomic force microscopy. microstructural properties high resolution x-ray diffraction. UV–visible spectroscopy exhibits clear blue shift due quantum confinement. photoluminescence spectra green...
Pentacene based junctions with Al on both p-Si(1 0 0) and indium tin oxide (ITO) substrates have been analysed using impedance spectroscopy (100 Hz–20 MHz) dc-current versus voltage measurements. Conduction mechanisms match well the space charge limited current model exponential trap distributions. Impedance studies reveal Schottky behaviour for devices. The differences between p-Si/pentacene/Al ITO/pentacene/Al devices explained by modelling equivalent circuits, one two RC elements,...
Metal-oxide-semiconductor capacitors with a trilayer structure consisting of Ge+HfO2 layers sandwiched between HfO2 tunnel and cap oxides were fabricated on p-Si substrates. Ge nanocrystals embedded in SiO2 also studied for comparison. Cross-sectional transmission electron micrographs revealed the formation spherical shaped nanocrystals. The optical charge storage characteristics structures through photoluminescence spectroscopy capacitance-voltage measurements, respectively. An enhancement...
We report on the observation of intraband near infrared (∼3.1 μm) and mid (∼6.2 photocurrent response at room temperature using Ge/Si self-assembled quantum dots grown by molecular beam epitaxy. Due to bimodal size distribution SiGe intermixing, distinguishable photoluminescence transitions are observed 10 K, below above optical band gap bulk Ge. The redshift in with increasing has been explained excitonic electric field originated due excitation low temperatures. A good correlation between...
The structural and optical properties of Ge quantum dots (QDs) grown on Si(001) for mid-infrared photodetector nanocrystals embedded in oxide matrices floating gate memory devices are presented. infrared photoluminescence (PL) signal from islands has been studied at a low temperature. temperature- bias-dependent photocurrent spectra capped Si/SiGe/Si(001) QDs device different size density high-k using radio frequency magnetron sputtering have studied. Transmission electron micrographs...
Size-dependent photoluminescence characteristics from Ge nanocrystals embedded in different oxide matrices have been studied to demonstrate the light emission visible wavelength quantum-confined charge carriers. On other hand, energy transfer mechanism between Er ions and has exploited exhibit optical fiber communication range. A broad electroluminescence, attributed electron hole recombination of injected carriers nanocrystals, achieved. Nonvolatile flash-memory devices using nanocrystal...
Organometal halide perovskite materials are presently some of the pacesetters for light harvesting in hybrid photovoltaic devices because their excellent inherent electrical and optical properties. However, long-term durability such remains a major bottleneck commercialization especially countries with hot humid climatic conditions, thus violating international standards technology. Albeit, TiO2 as an electron-transport layer has been well investigated solar cells; high-temperature...
Magnetic Barkhausen noise (MBN) measurements were made on a sample of pipeline steel as functions magnetizing frequency and AC flux density in the sample. The observed MBN responses suggest strong dependence these parameters. With increasing sample, activity initially increases but finally begins to decrease at higher magnitudes density. also with frequency. Pulse-height distribution analysis waveforms suggests that magnetization parameters is more complex than appears from rms voltage...
CdS nanocomposites have been grown in a polymer (polyvinyl alcohol) matrix using simple chemical bath deposition process. Transmission electron micrographs of at different solution temperatures revealed the formation isolated as well junctionlike structures. X-ray and selected area diffraction patterns show that are polycrystalline with cubic phase. Optical band gaps nanocomposite films found to decrease (3.26–2.86eV) increase temperature from 70to90°C. Photoluminescence spectra strong green...
We present the first systematic study of a two-moded erbium-doped fiber amplifier, and identified its performance trends. By optimizing dopant distribution pump modes we achieved over 22dB gain for both LP01 LP11-modes.
Ultrathin ZrO2 gate dielectrics have been deposited on strain-compensated Si0.69Ge0.3C0.01 layers by rf magnetron sputtering. High-resolution transmission electron microscopy along with energy-dispersive x-ray spectroscopy and photoelectron show the formation of a polycrystalline an amorphous Zr–germano–silicate interfacial layer between oxide SiGeC films. A dielectric constant 17.5 for 7.0 interfacial-silicate calculated from high-frequency capacitance–voltage measurements. These equivalent...