ardhendu saha - Academia.edu (original) (raw)

Papers by ardhendu saha

2015 International Conference on Green Computing and Internet of Things (ICGCIoT)

This paper proposes a single-stage inverter topology for grid connected PV systems. Isolated volt... more This paper proposes a single-stage inverter topology for grid connected PV systems. Isolated voltage generated by the solar modules is effectively used in a neutral point clamped multilevel inverter to generate high quality AC voltage for feeding into the grid. The control scheme is implemented in synchronously rotating reference frame for independent control of active and reactive power. Loss calculation and THD analysis is done for 2 level, 3 level, 5 level and 7 level inverter and an optimal number of level in achieved for a given voltage and power rating.

Applied Physics B, 2016

diffractive corrections such as Goos-Hänchen (GH) shift and Imbert-Fedorov (IF) shift [1]. GH shi... more diffractive corrections such as Goos-Hänchen (GH) shift and Imbert-Fedorov (IF) shift [1]. GH shift is the longitudinal displacement occurring in the plane of incidence relative to the geometric optics position for an incident linearly polarized beam [2]. For elliptically polarized incident beam, two simultaneous shifts occur: Transverse IF shift that is orthogonal to the plane of incidence with respect to geometric optics position along with the Longitudinal GH shift [3, 4]. The wide area of applications of the GH shift and the IF shift has made these shifts technically significant in the recent years [5-7]. Both the GH shift and the IF shift are polarization-dependent and manifest a spatial character elucidating the displacement of the beam with respect to the geometrical ray and an angular character depicting the angular deviation of the beam from the law of specular reflection θ incident = θ reflection [8, 9]. The extremely small magnitudes of these shifts as compared to the finite transversal extent of the incident beam have limited their applications mostly to laboratories [10]. A great deal of literature exists about the endeavor to enhance these shifts by exploring new optical structures with various materials and configurations at a wavelength other than the telecommunication wavelength within C-band (1550 nm) [11-21]. The magnitude of these shifts can also be magnified by utilizing long-range surface-plasmon polariton (LRSPP) resonance phenomenon [22]. Surface-plasmon polaritons (SPPs) are transverse magnetic (TM) polarized optical surface waves that propagate along a metal-dielectric interface [23]. LRSPP is formed by coupling of two SPPs at the opposite boundary of a metal film sandwiched between two semiinfinite dielectric media [24]. The ability of LRSPP resonance to probe refractive index changes occurring within the immediate vicinity of the metal surface along with its potential to effectively confine the electromagnetic fields into a nanoscale volume near metal-dielectric interface Abstract A proposition toward all-optical tuning of longrange surface-plasmon-enhanced beam shifts and all-optical switching is implemented analytically by exploitation of Kerr effect induced refractive index change through varying pump light intensity in a multilayer long-range surface-plasmon configuration at 1550 nm. Through the optimized design comprising polydiacetylene para-toulene sulfonate as a Kerr polymer, a high-contrast all-optical switch with a pump intensity threshold of 0.15 GW/cm 2 is proposed. The design also provides giant spatial and angular Goos-Hänchen and Imbert-Fedorov shifts at mm and µrad ranges along with wide range of tunability of beam shifts with the varying pump light intensity and the varying incident angle. Moreover, exact beam position and beam steering considering the conjoint effect of spatial and angular Goos-Hänchen and Imbert-Fedorov shifts for different incident polarizations are also obtained. This idea proffers a new possibility for pulse generation, optical sensors applications, optical modulation, geodetic surveying, etc.

Superlattices and Microstructures, Nov 1, 2017

Theoretically, the transmission properties of a symmetric double-negative metamaterial one-dimens... more Theoretically, the transmission properties of a symmetric double-negative metamaterial one-dimensional photonic crystal containing an extrinsic random layer thickness magnetized cold plasma photonic quantum-well defect structure have been investigated. From the numerical results performed by characteristics matrix method, it is found that, such type of structure possesses a transmission peak within the zero-gap. To design a tunable microwave filter, the effects of many parameters such as randomness of layer thickness of the multilayer defect in terms of standard deviation (), strength of external magnetic field () and electron density of magnetized cold plasma () on transmission peak is discussed. Our findings show that the histogram for the central frequency of the transmission peaks becomes wider with respect to smaller values of. In addition, in the case of , our investigations also reveal that the histogram shifts to the higher frequency range and vice versa while considering the case of. These findings help to design a tunable filter for different microwave applications.

PROCEEDINGS OF THE 2022 4TH INTERNATIONAL CONFERENCE ON SUSTAINABLE MANUFACTURING, MATERIALS AND TECHNOLOGIES

SPIE Future Sensing Technologies

Bend-induced loss in microbending fiber-optic sensor has proved to be an effective one for the di... more Bend-induced loss in microbending fiber-optic sensor has proved to be an effective one for the direct and indirect measurement of various physical parameters. In this research, a novel and highly sensitive microbend sensor has been explored by launching a zero order Bessel-Gauss beam inside a waveguide arrangement having a No-core fiber bonded amidst two special higher-order mode supporting fibers. By harnessing the special characteristics of the Bessel-Gauss beam, pairing of manifold high-order modes has been affirmed inside the sensor structure. The captivating feature of such sensor is that it defies the conventional wisdom and significantly improves the sensitivity without any intricate fabrication techniques like in tapering, bending etc. To our knowledge, such realization of Bessel-Gauss beam-shined microbend sensor has not been reported earlier in any of the contemporary literature. In support of our theoretical analysis; a Beam propagation method is employed in OptiBPM software (Optiwave Systems Inc.) to envisage the full transmission spectrum of the waveguide. For different bend radii, the sensor response has been numerically investigated and it is anticipated that the sensitivity is expected to be enhanced by a gentle reduction in the bend radius. With the presence of six microbends, the proposed sensor manifests an average bend sensitivity of 2.8 dB/mm which is 3.2 times superior to the classical microbend sensing configuration. Due to such superior sensing performance, the present paradigm paves the way for many potential applications, like damage detection of various engineering structures, and measurement of different physical parameters like temperature and pressure.

Journal of the Optical Society of America B

This paper deals with the development of an effective theoretical approach to generate spatial op... more This paper deals with the development of an effective theoretical approach to generate spatial optical soliton in exceptionally beneficial bulk beta-barium-borate crystal by utilizing cascaded second-order nonlinearity through electro-optic tuning. The proposed methodology paves the way for novel nonlinear optical interactions conceptualized in bulk material depending upon an effective nonlinear refractive index for a broad range of crystal lengths. The development of ( 2 + 1 ) D spatial bright soliton has been analytically demonstrated at 800 nm wavelength of the incident continuous-wave optical radiation, and the implication of tunable electro-optic effect to the crystal’s nonlinear response is also presented here. Involvement of the generalized nonlinear Schrödinger equation has been utilized to develop the necessary and sufficient criteria for self-trapping optical beams considering both linear and nonlinear absorption losses. In conformity with the findings of the simulation, t...

2022 Workshop on Recent Advances in Photonics (WRAP)

A multilayered modified Otto configuration assisting graphene symmetric mode resonance is analyti... more A multilayered modified Otto configuration assisting graphene symmetric mode resonance is analytically explored to achieve low threshold optical bistability of about 2.5×105 V/m at 1 THz frequency. Through the proposed configuration, the effect of layer-number of spatially separated graphene sheets on the phenomenon of hysteresis is also investigated and has been found that the graphene symmetric mode resonance can be optimized through the variation of graphene layer-number, which will lead to minimal demand of input power for realizing the optical bistability using the suggested model. The proposed system offers promising applications in the realm of all-optical integrated devices.

Optik

Abstract Curiosity in the properties of non-Gaussian beam-based optical devices has seen a recent... more Abstract Curiosity in the properties of non-Gaussian beam-based optical devices has seen a recent resurgence on account of large volume of higher order modes as supported by the platform. By harnessing the advantages of higher-order Bessel-Gauss beam, the present research unveils the concept of an extremely-sensitive optical sensor to detect the limit of kerosene adulteration in petrol. The sensory method works on the concept of modal interference, in which the transmitted power differs with changeable cladding refractive index as induced by the varying kerosene concentration in petrol. To corroborate this, the commercially available Lumerical’s Mode solution software and its Eigenmode expansion solver were exploited to investigate the transmitting property of the sensing device. If the sensing length is set to 7 cm, the procured average sensitivity of 0.41 dB/% is 4.1-fold higher in contrast to the typical Gaussian beam-shined sensor. The presence of ~0.02% kerosene contaminant in petrol can be sensed with the proposed methodology, while the conventional Gaussian beam-shined technology is able to sense the presence of ~0.10% of the same. Therefore such a nascent-class of beam called higher-order Bessel-Gauss beam accelerates new possibilities in the area of fiber optic sensing and can be useful in various petrochemical and automotive industries.

Springer Proceedings in Physics, 2022

2020 2nd International Conference on Innovative Mechanisms for Industry Applications (ICIMIA), 2020

This paper explores a comprehensive study at the application of second harmonic generation in low... more This paper explores a comprehensive study at the application of second harmonic generation in low power laser generation by introducing electro-optically adjustable nonlinear phase shift inside a LiNbO3 crystal. Research on electro-optically adjustable nonlinear phase shift in high power laser generation is completed already by way of the usage of special crystals having higher electro-optic coefficients and higher damage threshold. However, crystal having lower damage threshold can withal be habituated to create this mentioned phenomenon if having better electro-optic coefficients. Hence, on this paper the advanced traits of LiNbO3 like higher electro-optic coefficients and lower damage threshold that makes this crystal very much handy to increase cascaded nonlinearity in low power laser generation are proposed. As consistent with our theoretical analysis, the propagating fundamental wave is oscillating at 1064 nm parallel to y-axis of the crystal having crystal cut at theta=67.14737circ\theta=67.14737^{\circ}theta=67.14737circ and phi=90circ\phi=90^{\circ}phi=90circ in phase matching direction. A analytical voltage of ±2.5 kV is applied across the crystal's thickness of 5 mm along z-axis of the crystal that creates the phase shift in between the incident and reconveretd fundamental waves which is nonlinear in nature. This nonlinear phase shift can be facilely tuned from maximum to minimum value by adjusting the applied external electric field.

Lecture Notes in Electrical Engineering, 2020

A proposal towards analytical implementation of optical bistability in a multilayered configurati... more A proposal towards analytical implementation of optical bistability in a multilayered configuration comprising a ZnSe prism, 1-µm-thick PMMA-DR1 (Polymethylmethacrylate-Disperse red) as dielectric layer, nano-Ag: polymeric composite material as a Kerr polymer and a 15-nm thin film of silver which is sandwiched between the dielectric layer and the Kerr polymer at incident light wavelength of 1550 nm with a beam waist of 0.5 mm is presented at 25 °C temperature. Here, the nonlinear Kerr medium is having quadratic dependence on the long-range surface plasmon polariton mode resonance-enhanced local electric field amplitude. Through the larger nonlinear effect of the optimized design by employing high local field effect in the nonlinear regime, a low threshold optical bistability of about 1.6 MW/cm2 in the transmitted light intensity is achieved. The reported threshold is less compared to the previous efforts where the works were carried out with a wavelength other than the important telecommunication wavelength within the C-band. The design also provides tunability of bistable threshold by exploitation of Kerr effect-induced refractive index change through varying pump light intensity. The proposed system proffers potential applications in all-optical networks.

Applied Physics B, 2021

We propose an electro-optically controllable cascaded second-order optical process that mimics as... more We propose an electro-optically controllable cascaded second-order optical process that mimics as a third-order nonlinear process which is utilized for the compression of ultrashort pulses. Effective compression of optical pulses has been achieved by making efficient use of frequency doubling into an extraordinarily advantageous crystal like beta-barium-borate which is capable of generating shorter pulses within a few cycles. In accordance with simulation, it endeavors ≈ threefold compression in femtosecond pulse, i.e., 47 fs has been achieved by applying a voltage of ∓ 6.2 kV which delivers a phase mismatch (Δk) = ± 117.236 m−1 and effective cascaded refractive index (n2cascade) of ± 3.045 × 10–20 m2/W. This competent compression leads to an increase in the value of peak intensity from 50 to 288 GW/cm2. On account of the decent control in peak intensity, this promising methodology can be utilized for advanced scientific research, and also implemented easily in a large variety of a...

A Novel proposal towards the surface plasmon enhanced optical amplification is proposed, designed... more A Novel proposal towards the surface plasmon enhanced optical amplification is proposed, designed and simulated in Kretschmann geometry formed by a 500 µm thick, 10 mm long and 5 mm wide BK7 parallel slab and 29 nm thin gold layer (n=0.38+10.75i) which is sandwiched between the said parallel slab and 20 nm thin GaAs layer (n=3.377). This GaAs layer is pumped by 1319 nm higher order Gaussian beam of a Nd:YAG laser, which passes through a cylindrical lens thereby generating a high aspect ratio elliptical cross section to attain intensity dependent negative extinction coefficient on that 3 mm long strip of irradiated GaAs. The negative extinction coefficient of GaAs layer facilitates the amplification of the incident optical radiation at 1550 nm within the communication window at 26 ° C temperature. Here the incident pulsed optical radiation of 5 mW is amplified to 274 MW through external pumping and surface plasmon resonance phenomenon by total internal reflection with three bounces a...

2016 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES), 2016

A multilevel inverter based single stage grid connected solar PV system is proposed in this paper... more A multilevel inverter based single stage grid connected solar PV system is proposed in this paper so as to reduce THD of the inverter voltage and reduce the size of filter circuit. A maximum power point tracking algorithm is implemented to obtain optimal performance of solar cell at different irradiance and temperature. Independent control of active and reactive power flow from inverter to the grid is obtained by implementing the control scheme in synchronously rotating reference frame. For interfacing the PV cell to the grid a 5kVA 3phase 3 level NPC Inverter is designed and fabricated. Space vector modulation scheme is used to generate the switching pulses for the inverter. Redundant switching states of a three level inverter are judiciously chosen to obtain capacitor voltage balancing. One of the most attractive features of a multilevel inverter is that it can generate output voltages with lower value of harmonic distortion and hence filter requirement is less. For hardware implementation the control scheme is implemented with a DSP. Complete scheme is simulated in MATLAB/ Simulink and verified in a 5kVA laboratory prototype.

International Journal of Modern Physics B, 2019

By using the transfer matrix method, the theoretical investigation has been carried out in the ne... more By using the transfer matrix method, the theoretical investigation has been carried out in the near- and mid-infrared bandgaps for a periodic multilayered structure that was composed of superconductor (SC) and semiconductor-metamaterial. It was found that two bandgaps appeared within the computational regions which are effectively optimized by manipulating the thickness of the SC film, fill factor of the semiconductor-metamaterial and the incidence angle of the incident electromagnetic wave. However, the thickness of the SC film and fill factor of the semiconductor-metamaterial are responsible for the red-shift of bandgaps, while the blue-shift is accounted for by the angle of incidence for both transverse electric (TE) and transverse magnetic (TM) waves. It is notable, for the TM wave, that the bandgaps disappeared at the incident angles of approximately 60[Formula: see text]. Such properties are quite useful in designing any new types of edge filters and other optical devices in t...

Optik - International Journal for Light and Electron Optics, 2017

Optics Communications, 2017

A new theoretical approach towards the composite effect of spatial and angular Goos-Hanchen (GH) ... more A new theoretical approach towards the composite effect of spatial and angular Goos-Hanchen (GH) shift and Imbert-Fedorov (IF) shift for the Gaussian beam, Laguerre-Gaussian beam and Bessel beam with long range surface plasmon (LRSP) resonance is observed, designed and simulated through the variation of incident angle at a wavelength of 1550 nm where the four layered Kreschmann-Rather geometry comprises a ZnSe prism, a liquid crystal layer of E44 and two metal layers of silver. To the best of our knowledge several articles have been devoted, separately considering the Gaussian beam, Laguerre-Gaussian beam and Bessel beam without considering the effect of spatial and angular GH shift and IF shift whereas the exact output beam position can only be identified with the composite effect of these shifts. The investigation of these spatial and angular shifts for Gaussian beam and different orders of Laguerre-Gaussian beam are calculated and represented where these lateral shifts increase with the increment of the modes and further these lateral shifts for Bessel beam have also been analyzed. With this new approach various avenues expedite the way of futuristic applications in the field of fine tuning in optical switching with the accurate beam position using different beams.