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Your search keyword '"Chattopadhyay, Sanatan"' showing total 47 results
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47 results on '"Chattopadhyay, Sanatan"'

3. Light-activated memristor by Au-nanoparticle embedded HfO$_2$-bilayer/p-Si MOS device

Author

Sengupta, Ankita, Chowdhury, Basudev Nag, Roy, Bodhishatwa, Satpati, Biswarup, Bhunia, Satyaban, and Chattopadhyay, Sanatan

Subjects
Physics - Applied Physics, Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The current work proposes a novel scheme for developing a light-activated non-filamentary memristor device by fabricating an Au-nanoparticle embedded HfO$_2$-bilayer/p-Si MOS structure. Under illumination, the electrons in such embedded Au-nanoparticles are excited from d-level to quantized s-p level and are swept out on application of an appropriate gate bias, leaving behind the holes without recombination. Such photogenerated holes are confined within the nanoparticles and thus screen the external field to lead to a memristive effect in the device. The phenomenon is experimentally observed in the fabricated Pt/HfO$_2$-(layer-II)/Au-NPs/HfO$_2$-(layer-I)/p-Si devices, where such memristive effect is activated/deactivated by light pulses. The memory window and high-to-low resistance ratio of the device are obtained to be ~1 V and ~10, respectively, which suggest the performance of a standard state-of-the-art memristor. Further, the present device offers a voltage-sweep-endurance up to at least 150 cycles and the memory retention up to ~10,000 s. Such a device concept can be extended for a combination of different nanoparticles with various dimensions and dielectric layers to optimize their memristive effect for achieving CMOS-compatible memory devices with superior reliability.

Published
2023

4. Design aspects of dual gate GaAs nanowire FET for room temperature charge qubit operation: A study on diameter and gate engineering

Author

Paul, Nilayan, Chowdhury, Basudev Nag, and Chattopadhyay, Sanatan

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Quantum Physics
Abstract

The current work explores a geometrically engineered dual gate GaAs nanowire FET with state of the art miniaturized dimensions for high performance charge qubit operation at room temperature. Relevant gate voltages in such device can create two voltage tunable quantum dots (VTQDs) underneath the gates, as well as can manipulate their eigenstate detuning and the inter-dot coupling to generate superposition, whereas a small drain bias may cause its collapse leading to qubit read out. Such qubit operations, i.e., Initialization, Manipulation, and Measurement, are theoretically modeled in the present work by developing a second quantization filed operator based Schrodinger-Poisson self-consistent framework coupled to non-equilibrium Greens function formalism. The study shows that the Bloch sphere coverage can be discretized along polar and azimuthal directions by reducing the nanowire diameter and increasing the inter-dot separation respectively, that can be utilized for selective information encoding. The theoretically obtained stability diagrams suggest that downscaled nanowire diameter and increased gate separation sharpen the bonding and anti-bonding states with reduced anticrossing leading to a gradual transformation of the hyperbolic current mapping into a pair of straight lines. However, the dephasing time in the proposed GaAs VTQD-based qubit may be significantly improved by scaling down both the nanowire diameter and gate separation. Therefore, the present study suggests an optimization window for geometrical engineering of a dual gate nanowire FET qubit to achieve superior qubit performance. Most importantly, such device is compatible with the mainstream CMOS technology and can be utilized for large scale implementation by little modification of the state of the art fabrication processes.

Published
2023

8. Sputtered HfO2/ZrO2 Induced Interfacial Ferroelectric HZO Layer for Negative Capacitance Applications

Author

Sengupta, Ankita, Nag Chowdhury, Basudev, Roy, Bodhishatwa, Sikdar, Subhrajit, Chattopadhyay, Sanatan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Giri, Chandan, editor, Iizuka, Takahiro, editor, Rahaman, Hafizur, editor, and Bhattacharya, Bhargab B., editor

Published
2023
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9. Investigating the Impact of Ge-Quantum Well Width in Si/SiO2/Ge/SiO2/Pt Resonant Tunneling Device with NEGF Formalism

Author

Paul, Nilayan, Nag Chowdhury, Basudev, Chattopadhyay, Sanatan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Giri, Chandan, editor, Iizuka, Takahiro, editor, Rahaman, Hafizur, editor, and Bhattacharya, Bhargab B., editor

Published
2023
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10. Comparative Analysis of Normal and Anemic RBC by Employing Impedimetric and Voltammetric Studies

Author

Bhattacharya, Debopam, Roy, Aindrila, Das, Chirantan, Nag Chowdhury, Basudev, Karmakar, Anupam, Chattopadhyay, Sanatan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Giri, Chandan, editor, Iizuka, Takahiro, editor, Rahaman, Hafizur, editor, and Bhattacharya, Bhargab B., editor

Published
2023
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11. Voltammetric Detection and Controlled Inhibition of Decarboxylation of Gallic Acid (GA) in Green Tea Using Eugenol

Author

Roy, Aindrila, Bhattacharya, Debopam, Das, Chirantan, Nag Chowdhury, Basudev, Karmakar, Anupam, Chattopadhyay, Sanatan, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Giri, Chandan, editor, Iizuka, Takahiro, editor, Rahaman, Hafizur, editor, and Bhattacharya, Bhargab B., editor

Published
2023
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17. Growth of Si-incorporated TiO2 thin films using Vapor–Liquid–Solid (VLS) method for room temperature CO2 sensing.

Author

Roy, Bodhishatwa, Das, Chirantan, Sharma, Jay, Bhuniya, Satyaban, Tiwari, Aditya, Kanungo, Sayan, Karmakar, Anupam, and Chattopadhyay, Sanatan

Abstract

The current work reports the room temperature sensing of CO2 by growing Si-incorporated TiO2 thin films on Si-substrate with enhanced sensing response. The study suggests that the incorporation of SiO2 in TiO2 lattice can be used to manipulate its defect states which alter the electrical conductivity of TiO2 from n-type to p-type. The TiO2 and Si-incorporated TiO2 thin films are grown on Si-substrate at 250 °C by VLS method. FESEM images confirm the formation of a continuous film and the XRD analysis of such thin films indicates transformation of crystalline anatase TiO2 to amorphous nature upon Si incorporation. The incorporation of Si within TiO2 also results in the formation of oxygen related vacancy states along with the reduction of Ti related vacancies within the TiO2 lattice. Such defect states have been investigated by performing absorption spectroscopy, room temperature PL measurements and XPS analysis. The 50% Si-incorporated TiO2 thin film is observed to provide a sensing response of 198% at 200 sccm CO2 flow rate which is only 2.54% for TiO2 thin film when measured at room temperature with ~ 47% relative humidity. However, such room temperature sensing response decreases with the increase of relative humidity and found to be 73% when the relative humidity is increased to 85%. Furthermore, such Si-incorporated TiO2 sensors exhibit a fast response and recovery time of 5.7 s and 3.6 s, respectively. Therefore, the 50% Si-incorporated TiO2 thin film-based sensors can be efficiently used for room temperature CO2 sensing by utilizing a simple cost-effective fabrication technique. [ABSTRACT FROM AUTHOR]

Published
2024
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18. Dual parameter smart sensor for nitrogen and temperature sensing based on defect-engineered 1T-MoS2.

Author

Ali, Mir Sahanur, Ali, Mir Sahidul, Mallick, Subhasish, Bhandari, Shubhranshu, Ali, Mir Intaj, Hazra, Subhenjit, Roy, Bodhishatwa, Chattopadhyay, Sanatan, Karmakar, Srikanta, and Chattopadhyay, Dipankar

Subjects
SCANNING transmission electron microscopy, INTELLIGENT sensors, MOLYBDENUM disulfide, POINT defects, GAS detectors
Abstract

In general, defects are crucial in designing the different properties of two-dimensional materials. Therefore large variations in the electric and optical characteristics of two-dimensional layered molybdenum disulphide might be attributed to defects. This study presents the design of a temperature and nitrogen sensor based on few-layer molybdenum disulfide sheets (FLMS), which was developed from bulk MoS2 (BMS) through an exfoliation approach. The produced sulfur defect, molybdenum defect, line defect, and plane defect were characterized by scanning transmission electron microscopy (STEM), which substantially impacts the sensing characteristics of the resulting FLMS. Our theoretical analysis validates that the sulfur vacancies of the MoS2 lattice improve sensing performance by promoting effective charge transfer and surface interactions with target analytes. The FLMS-based sensor showed a high sensitivity for detecting nitrogen gas with a detection limit (LOD) of ~ 0.18 ppm. Additionally, temperature-detecting capabilities were assessed over various temperatures, showing outstanding stability and repeatability. To the best of our knowledge, this material is the first of its kind, demonstrating visible N2 gas sensing with chromic behaviour. [ABSTRACT FROM AUTHOR]

Published
2024
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23. Investigation of Highly Efficient Dual-Band Photodetector Performance of Spin-on-Doping (SOD) Grown p-Type Phosphorus Doped ZnO (P:ZnO)/n-Ga2O3 Heterojunction Device

Author

Mishra, Madhuri, Saha, Rajib, Saha, Archishman, Dalal, Avijit, Sengupta, Ankita, Mondal, Aniruddha, Chattopadhyay, Sanatan, and Chakrabarti, Subhananda

Abstract

We developed a stable and reproducible p-type P:ZnO thin film using a cost-effective solution-derived spin-on-doping (SOD) technique. We created a pure p-n heterojunction by depositing a highly transparent Ga2O3 thin film on P:ZnO for photodetector applications. The films’ surface morphology and thickness were analyzed using AFM and FEGSEM. At the same time, UV-visible (UV–Vis) and PL spectroscopy were employed to investigate their optical properties, including absorption, energy bandgap, and defect-related carrier transitions. The resulting P:ZnO/Ga2O3 heterojunction demonstrated excellent photo-response performance, with a responsivity of 4.76 A/W, detectivity of $10.13\times 10^{{12}}$ Jones, and rapid response speed. The device exhibited sensitivity to UV-C and UV–Vis wavelength regions, showcasing its potential for high-performance, dual-band, and low-power photodetectors.

Published
2024
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35. Investigation of Yttrium (Y)-doped ZnO (Y:ZnO)–Ga2O3 core-shell nanowire/Si vertical heterojunctions for high-performance self-biased wideband photodetectors.

Author

Saha, Rajib, Chakrabarti, Subhananda, Karmakar, Anupam, and Chattopadhyay, Sanatan

Abstract

High interfacial area, less surface defects and wide light absorption capability of core-shell nanowire heterojunctions are broadly accepted as a potential candidate for self-biased, high-speed photodetectors. In the current study, Y:ZnO–Ga2O3 core-shell nanowires' heterojunctions are fabricated by employing sequential double-step chemical bath deposition (CBD) and radio -frequency (RF) sputtering techniques on Si substrate. The ultra-thin highly transparent Ga2O3 (~ 15 nm) layer reduces the surface states of Y:ZnO nanowires in a significant amount and such core-shell heterojunction deals with the development of low power white light-responsive detectors by combining Y:ZnO and Ga2O3. The crystallinity, structure, chemical states and light absorption properties of the Y:ZnO–Ga2O3 core-shell nanowires are analysed in detail by using XRD, FESEM, HRTEM, EDS, XPS and UV-Visible spectroscopy. The fabricated core-shell Y:ZnO–Ga2O3 nanowire/Si heterojunction exhibits p–n junction behaviour and it exhibits self-powered photoresponse under Xe lamp with AM 1.5 G (100 W/cm2) filter. A low dark current of ~ 1.74 × 10− 11 A, high photo-to-dark current ratio of 3.2 × 104 and rapid response speed of < 1 s are achieved from such core-shell heterojunction device and relevant photo-carrier generation mechanism is considered from energy band diagram. Therefore, current study provides a technological route to fabricate the next-generation self-powered core-shell heterojunction devices for photo-sensing applications. [ABSTRACT FROM AUTHOR]

Published
2023
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38. Impact of deposition temperature on crystalline quality, oxygen vacancy, defect modulations and hetero-interfacial properties of RF sputtered deposited Ga2O3 thin films on Si substrate.

Author

Saha, Rajib, Bhowmick, Sangita, Mishra, Madhuri, Sengupta, Ankita, Chattopadhyay, Sanatan, and Chakrabarti, Subhananda

Subjects
THIN films, RADIOFREQUENCY sputtering, OPTOELECTRONIC devices, IMAGING systems in chemistry, X-ray photoelectron spectroscopy, CHEMICAL properties, ATOMIC force microscopy, RADIO frequency
Abstract

In the current work, thin film (∼55 nm) of n-type Ga2O3 (n-Ga2O3) is deposited on silicon (p-Si) substrate by using radio-frequency (RF) sputtering technique with systematic substrate temperature variations (room temperature to 700 °C). The structural, optical properties and chemical states of elements of the deposited films are observed to depend significantly on the deposition temperatures. The chemical composition and oxidation states, optical properties, defect states and structural quality of the deposited films are investigated in detail by employing x-ray photoelectron spectroscopy, energy dispersive x-ray, spectroscopic ellipsometry, Raman, photoluminescence and atomic force microscopy images. X-ray diffraction result reveals a polycrystalline nature of monoclinic β -phase of Ga2O3 with (403) dominant plane. The work functions are calculated from the ultraviolet photo-electron spectroscopy for all the deposited films and Ga2O3/Si heterojunction properties are investigated by using currentâ€"voltage (I â€" V) and capacitanceâ€"voltage (C â€" V) measurements. Among all the fabricated heterojunctions, 600 °C deposited Ga2O3 film exhibits superior performance in terms of energy bandgap, work function, refractive index, barrier height, rectification ratio and effective carrier concentrations. The current transport mechanism is analysed using the appropriate energy band diagram of Ga2O3 and Si. Therefore, the study suggests that 600 °C deposition temperatures is the optimum temperature for developing a high quality Ga2O3 thin film on Si by using RF sputtering technique and corresponding Ga2O3 thin film/Si heterojunction can be a potential candidate for developing several electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Published
2022
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46. Dual parameter smart sensor for nitrogen and temperature sensing based on defect-engineered 1T-MoS2.

Author

Ali, Mir Sahanur, Ali, Mir Sahidul, Mallick, Subhasish, Bhandari, Shubhranshu, Ali, Mir Intaj, Hazra, Subhenjit, Roy, Bodhishatwa, Chattopadhyay, Sanatan, Karmakar, Srikanta, and Chattopadhyay, Dipankar

Subjects
*SCANNING transmission electron microscopy, *INTELLIGENT sensors, *MOLYBDENUM disulfide, *POINT defects, *GAS detectors
Abstract

In general, defects are crucial in designing the different properties of two-dimensional materials. Therefore large variations in the electric and optical characteristics of two-dimensional layered molybdenum disulphide might be attributed to defects. This study presents the design of a temperature and nitrogen sensor based on few-layer molybdenum disulfide sheets (FLMS), which was developed from bulk MoS2 (BMS) through an exfoliation approach. The produced sulfur defect, molybdenum defect, line defect, and plane defect were characterized by scanning transmission electron microscopy (STEM), which substantially impacts the sensing characteristics of the resulting FLMS. Our theoretical analysis validates that the sulfur vacancies of the MoS2 lattice improve sensing performance by promoting effective charge transfer and surface interactions with target analytes. The FLMS-based sensor showed a high sensitivity for detecting nitrogen gas with a detection limit (LOD) of ~ 0.18 ppm. Additionally, temperature-detecting capabilities were assessed over various temperatures, showing outstanding stability and repeatability. To the best of our knowledge, this material is the first of its kind, demonstrating visible N2 gas sensing with chromic behaviour. [ABSTRACT FROM AUTHOR]

Published
2024
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47. Dual parameter smart sensor for nitrogen and temperature sensing based on defect-engineered 1T-MoS 2 .

Author

Ali MS, Ali MS, Mallick S, Bhandari S, Ali MI, Hazra S, Roy B, Chattopadhyay S, Karmakar S, and Chattopadhyay D

Abstract

In general, defects are crucial in designing the different properties of two-dimensional materials. Therefore large variations in the electric and optical characteristics of two-dimensional layered molybdenum disulphide might be attributed to defects. This study presents the design of a temperature and nitrogen sensor based on few-layer molybdenum disulfide sheets (FLMS), which was developed from bulk MoS 2 (BMS) through an exfoliation approach. The produced sulfur defect, molybdenum defect, line defect, and plane defect were characterized by scanning transmission electron microscopy (STEM), which substantially impacts the sensing characteristics of the resulting FLMS. Our theoretical analysis validates that the sulfur vacancies of the MoS 2 lattice improve sensing performance by promoting effective charge transfer and surface interactions with target analytes. The FLMS-based sensor showed a high sensitivity for detecting nitrogen gas with a detection limit (LOD) of ~ 0.18 ppm. Additionally, temperature-detecting capabilities were assessed over various temperatures, showing outstanding stability and repeatability. To the best of our knowledge, this material is the first of its kind, demonstrating visible N 2 gas sensing with chromic behaviour., (© 2024. The Author(s).)

Published
2024
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