Subhadra Chaudhuri
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Subhadra Chaudhuri has a total of 29 co-authors. Here are the top co-authors by number of shared publications:
- Supriya Chakrabarti
Nanotechnology & Integrated Bio-Engineering Centre, Ulster University, Newtownabbey, UK
6 shared publications S. Kar
Indian Association for the Cultivation of Science
3 shared publicationsA. Dev
Indian Association for the Cultivation of Science
2 shared publicationsA.K. Pal
Department of Materials Science, Indian Association for the Cultivation of Science, Calcutta-700 032, India
2 shared publicationsD Das
Inter-University Consortium for DAE Facilities, III/LB/8, Bidhan Nagar, Kolkata 700 098, India
2 shared publicationsD Ganguli
Department of Materials Science, Indian Association for the Cultivation of Science, Calcutta 700 032, India
2 shared publications
Latest Publications
- 1 February 2007
- Published by Elsevier in Journal of Crystal Growth
- Vol. 299 (1) , 94-102
Growth of different morphological features of micro and nanocrystalline manganese sulfide via solvothermal process
- 1 February 2007
- Published by Elsevier in Journal of Crystal Growth
- Vol. 299 (1) , 94-102
Growth of different morphological features of micro and nanocrystalline manganese sulfide via solvothermal process
- 7 July 2006
- Published by Springer Nature in Journal of Nanoparticle Research
- Vol. 8 (6) , 919-926
Synthesis and characterization of sol-gel derived Mn2+ doped In2S3 nanocrystallites embedded in a silica matrix
- 7 July 2006
- Published by Springer Nature in Journal of Nanoparticle Research
- Vol. 8 (6) , 919-926
Synthesis and characterization of sol-gel derived Mn2+ doped In2S3 nanocrystallites embedded in a silica matrix
- 15 January 2006
- Published by Elsevier in Materials Science and Engineering: B
- Vol. 126 (1) , 97-101
Optical characterization of In2S3–SiO2 nanocomposite thin films synthesized by sol–gel technique
- 15 January 2006
- Published by Elsevier in Materials Science and Engineering: B
- Vol. 126 (1) , 97-101
Optical characterization of In2S3–SiO2 nanocomposite thin films synthesized by sol–gel technique
- 16 August 2005
- Published by American Physical Society (APS) in Physical Review B
- Vol. 72 (7) , 075338
Finite-size effects on band structure of CdS nanocrystallites studied by positron annihilation
Quantum confinement effects in nanocrystalline CdS were studied using positrons as spectroscopic probes to explore the defect characteristics. The lifetime of positrons annihilating at the vacancy clusters on nanocrystalline grain surfaces increased remarkably consequent to the onset of such finite-size effects. The Doppler broadened line shape was also found to reflect rather sensitively such distinct changes in the electron momentum redistribution scanned by the positrons, owing to the widening of the band gap. The nanocrystalline sizes of the samples used were confirmed from x-ray diffraction and high resolution transmission electron microscopy and the optical absorption results supported the quantum size effects. Positron annihilation results indicated distinct qualitative changes between CdS nanorods and the bulk sample, notwithstanding the identical x-ray diffraction pattern and close resemblance of the optical absorption spectra. The results are promising in the event of positron annihilation being proved to be a very successful tool for the study of such finite-size effects in semiconductor nanoparticles.
- 16 August 2005
- Published by American Physical Society (APS) in Physical Review B
- Vol. 72 (7) , 075338
Finite-size effects on band structure of CdS nanocrystallites studied by positron annihilation
Quantum confinement effects in nanocrystalline CdS were studied using positrons as spectroscopic probes to explore the defect characteristics. The lifetime of positrons annihilating at the vacancy clusters on nanocrystalline grain surfaces increased remarkably consequent to the onset of such finite-size effects. The Doppler broadened line shape was also found to reflect rather sensitively such distinct changes in the electron momentum redistribution scanned by the positrons, owing to the widening of the band gap. The nanocrystalline sizes of the samples used were confirmed from x-ray diffraction and high resolution transmission electron microscopy and the optical absorption results supported the quantum size effects. Positron annihilation results indicated distinct qualitative changes between CdS nanorods and the bulk sample, notwithstanding the identical x-ray diffraction pattern and close resemblance of the optical absorption spectra. The results are promising in the event of positron annihilation being proved to be a very successful tool for the study of such finite-size effects in semiconductor nanoparticles.
- 1 July 2005
- Published by Taylor & Francis in Transactions of the Indian Ceramic Society
- Vol. 64 (3) , 133-136
Synthesis and Characterization of Sol-Gel Derived Cu Doped ZnO Films
Well-crystallized Cu doped (1,3 and 5 mol%) ZnO films were deposited on quartz substrates by sol-gel technique. The optical, microstructural and photoluminescence properties of the films were studied. It was found that the band gaps (3.38 eV) of the films did not vary up to 5% Cu doping in ZnO. The preferred orientation along (002) was observed for all the films and the degree of orientation decreased with increasing the molar percentage of Cu in ZnO. Atomic force microscopy (AFM) measurements were performed to study the surface morphology of 1,3 and 5% Cu doped ZnO thin films; the surface roughness of 1 mol% Cu doped ZnO film was smaller (∼6 nm) than those of 3 and 5 mol% Cu doped ZnO films (∼15-20 nm). The photoluminescence spectra of the films showed six peaks at 3.11, 3.03, 2.75, 2.68, 2.65 and 2.27 eV. One peak (3.11 eV) was due to excitonic transition and the other five peaks were due to defect related transitions. The excitonic peak intensity of Cu doped ZnO increased with increasing copper concentration.
- 1 July 2005
- Published by Taylor & Francis in Transactions of the Indian Ceramic Society
- Vol. 64 (3) , 133-136
Synthesis and Characterization of Sol-Gel Derived Cu Doped ZnO Films
Well-crystallized Cu doped (1,3 and 5 mol%) ZnO films were deposited on quartz substrates by sol-gel technique. The optical, microstructural and photoluminescence properties of the films were studied. It was found that the band gaps (3.38 eV) of the films did not vary up to 5% Cu doping in ZnO. The preferred orientation along (002) was observed for all the films and the degree of orientation decreased with increasing the molar percentage of Cu in ZnO. Atomic force microscopy (AFM) measurements were performed to study the surface morphology of 1,3 and 5% Cu doped ZnO thin films; the surface roughness of 1 mol% Cu doped ZnO film was smaller (∼6 nm) than those of 3 and 5 mol% Cu doped ZnO films (∼15-20 nm). The photoluminescence spectra of the films showed six peaks at 3.11, 3.03, 2.75, 2.68, 2.65 and 2.27 eV. One peak (3.11 eV) was due to excitonic transition and the other five peaks were due to defect related transitions. The excitonic peak intensity of Cu doped ZnO increased with increasing copper concentration.
- 1 June 2005
- Published by Springer Nature in Journal of Nanoparticle Research
- Vol. 7 (2-3) , 195-201
Optical properties of Mg0.05Zn0.95O/SiO2 nanocomposite films prepared by sol–gel technique
- 1 June 2005
- Published by Springer Nature in Journal of Nanoparticle Research
- Vol. 7 (2-3) , 195-201
Optical properties of Mg0.05Zn0.95O/SiO2 nanocomposite films prepared by sol–gel technique
- 28 February 2005
- Published by Elsevier in Materials Letters
- Vol. 59 (2-3) , 289-292
Synthesis of highly oriented iron sulfide nanowires through solvothermal process
- 28 February 2005
- Published by Elsevier in Materials Letters
- Vol. 59 (2-3) , 289-292
Synthesis of highly oriented iron sulfide nanowires through solvothermal process
- 22 February 2005
- Published by American Physical Society (APS) in Physical Review B
- Vol. 71 (6) , 064105
Positron annihilation lifetime changes across the structural phase transition in nanocrystallineNanocrystalline samples of were prepared through chemical routes and the particles were allowed to grow by thermal treatment at different temperatures. transformed to the phase at a temperature relatively lower than that reported for coarse-grained samples. Positron lifetimes were measured in both the phases of the samples and a significant reduction was observed across the transformation. This is attributed to the expected reduction in the unit cell volume and the nature of orientation of the nearest-neighboring atoms around the positron trapping sites. Positrons are basically annihilating from the octahedral vacancy sites in and the lifetime decreases as the nearest-neighboring atoms increasingly influence the annihilation probability of the positrons when the sample changes to the phase. The reduction in the positron lifetime has helped to envisage the onset of the transformation earlier than that indicated by x-ray diffraction. The positron lifetimes in the intergranular region increased due to the increase in free volume associated with the atoms on the grain surfaces when the grain size reduced. Doppler broadening measurements of the annihilation -ray spectral line shapes were also carried out and the results supported these findings.- 22 February 2005
- Published by American Physical Society (APS) in Physical Review B
- Vol. 71 (6) , 064105
Positron annihilation lifetime changes across the structural phase transition in nanocrystallineNanocrystalline samples of were prepared through chemical routes and the particles were allowed to grow by thermal treatment at different temperatures. transformed to the phase at a temperature relatively lower than that reported for coarse-grained samples. Positron lifetimes were measured in both the phases of the samples and a significant reduction was observed across the transformation. This is attributed to the expected reduction in the unit cell volume and the nature of orientation of the nearest-neighboring atoms around the positron trapping sites. Positrons are basically annihilating from the octahedral vacancy sites in and the lifetime decreases as the nearest-neighboring atoms increasingly influence the annihilation probability of the positrons when the sample changes to the phase. The reduction in the positron lifetime has helped to envisage the onset of the transformation earlier than that indicated by x-ray diffraction. The positron lifetimes in the intergranular region increased due to the increase in free volume associated with the atoms on the grain surfaces when the grain size reduced. Doppler broadening measurements of the annihilation -ray spectral line shapes were also carried out and the results supported these findings.- 14 January 2005
- Published by Wiley in Physica Status Solidi (a)
- Vol. 202 (3) , 441-448
Enhancement of UV luminescence in sol‐gel prepared ZnO thin films by incorporation of Mg
- 14 January 2005
- Published by Wiley in Physica Status Solidi (a)
- Vol. 202 (3) , 441-448
Enhancement of UV luminescence in sol‐gel prepared ZnO thin films by incorporation of Mg
- 25 October 2004
- Published by AIP Publishing in Applied Physics Letters
- Vol. 85 (17) , 3851-3853
Direct synthesis of single crystalline In2O3 nanopyramids and nanocolumns and their photoluminescence properties
Single crystalline indium oxide pyramid and column structures were synthesized by a simple physical evaporation technique. The pyramid structure was obtained without any catalytic action while the column structure was produced using gold as the catalyst. The nanostructures were characterized by x-ray diffraction, scanning electron microscopy and transmission electron microscopy. A blue-green photoluminescence band in the visible region was observed in the structures which could be ascribed to the existence of a large amount of singly ionized oxygen vacancies, confirmed by electron paramagnetic resonance.- 25 October 2004
- Published by AIP Publishing in Applied Physics Letters
- Vol. 85 (17) , 3851-3853
Direct synthesis of single crystalline In2O3 nanopyramids and nanocolumns and their photoluminescence properties
Single crystalline indium oxide pyramid and column structures were synthesized by a simple physical evaporation technique. The pyramid structure was obtained without any catalytic action while the column structure was produced using gold as the catalyst. The nanostructures were characterized by x-ray diffraction, scanning electron microscopy and transmission electron microscopy. A blue-green photoluminescence band in the visible region was observed in the structures which could be ascribed to the existence of a large amount of singly ionized oxygen vacancies, confirmed by electron paramagnetic resonance.