Referred Journal Publications :
(1)"Quantum well intermixed waveguide grating", R. Sonkar and U. Das, Optical and Quantum Electronics, 42, No.9-10, pp.631-643(Sept. 2011) (2) "Experimental Study of the Effects of Environmental and Fog Condensation Nuclei Parameters on the Rate of Fog Formation and Dissipation Using a New Laboratory Scale Fog Generation Facility", V. P. Singh, T. Gupta, S. N. Tripathi, C. Jariwala, and U. Das, Aerosol and Air Quality Res., 11, 140-154 (2011).(3) "Integrated MQW intermixed InGaAsP/InP waveguide photodiodes", T. Bhowmick and U. Das, Opt. and Quantum Electr., Springer, 42(2), pp109-120(2010), DOI:10.1007/s11082-010-9427-6, Published Online Dec. 09, 2010.
http://www.springerlink.com/content/l827vt2108g243u7/
(4) "Waveguide Grating Using Quantum Well Intermixing", R K Sonkar and U. Das, Intl. J. of Res. and Revs. in Appl. Sc., 5 , pp 43-51(Oct. 2010).
(5) "Optical Quality SiC nano-structures by Spin-On Technique and Anneal on Si", A Mondal and U Das, J. Phys. D: Appl. Phys. 42, 234002-234006 (2009).
(6) "Design of a Grating-Assisted Lateral Directional Coupler by Impurity-Induced Quantum Well Intermixing of InGaAs/GaAs", A. V. Barve and U. Das, Special Issue, joint publication of IEEE J. Lightwave Technol., 25, 2448(2007) and Optical Society of America.
(7) "Suspended Substrate Bias-T at 2.5-10GHz", U. Das, R. K. Joshi, D. Biswas, and A. Biswas, Microwave and Opt. Technol. Lett., 27, 444(2000).
(8) "F Induced Layer Disordering of GaAs/InGaP Quantum Wells", U. Das, B. Pathangey, Z. Osman, and T. J. Anderson, Appl. Phys. Lett.. 71, 1700(1997).
(9) "Luminescence and Deep Level Characteristics of GaAs/Si Atomic Layer Epitaxy grown Predeposition layers", M. Mazumdar, S. Dhar, and U. Das, J. Appl. Phys. 79, 8688(1996).
(10) "Atomic Layer Epitaxial Predeposition for GaAs growth on Si", U. Das, S. Dhar, and M. Mazumdar, Appl. Phys. Lett. 68, 3573(1996).
(11) "Strong Luminescence Intensities in Al0.22Ga0.78As grown on misoriented (111)B GaAs", A. Chin, T. M. Cheng, S. P. Peng, Z. Osman, U. Das, and C. Y. Chang, Appl. Phys. Lett. 63, 2381(1993).
(12) "CBE Growth of InP Using Triethylindium and Bisphosphinoethane", A. Chin, P. Martin, U. Das, J. Mazurowski, and J. Ballingall, J. Vac. Sci. Technol., B11, 847(1993).
(13) "Use of Triethylindium and Biphosphinoethane for the Growth of InP by Chemical Beam Epitaxy", A. Chin, P. Martin, U. Das, J. Mazurowski, and J. Ballingall, Appl. Phys Lett. 61, 2099(1992).
(14) "High Quality Materials and Heterostructures on (111)B GaAs", A. Chin, P. Martin, U. Das, J. Ballingall, and T.- H. Yu, J. of Vac. Sci. and Technol. B B10, 775 (1992).
(15) "Tailoring of Electron and Hole Energies in Strained GaAsP/AlGaAs Quantum Wells using Fluorine Impurity Induced Layer Disordering", U. Das, S. Davis, R. V. Ramaswamy, and F. A. Stevie, Appl. Phys. Lett. 60, 210 (1992).
(16) "Investigation of the Interface Region Produced by Molecular Beam Epitaxial Regrowth", D. Biswas, P. R. Berger, U. Das, J. E. Oh and P. K. Bhattacharya, J. Electron. Mater. 18, 137 (1989).
(17) "Orientation-Dependent Phase Modulation in InGaAs/GaAs Multiquantum Well Waveguides", U. Das, Y. Chen, P. K. Bhattacharya, and P. R. Berger, Appl. Phys. Lett. 53, 2129 (1988).
(18) "Growth and Properties of In0.52Al0.48As/In0.53Ga0.47As, GaAs:In and InGaAs/GaAs Multilayers", F-Y. Juang, W. P. Hong, P. R. Berger, P. K. Bhattacharya, U. Das, and J. Singh, J. Cryst. Growth 81, 373 (1987).
(19) "III-V Superlattice Photodiodes", F-Y. Juang, W. Li, P. K. Bhattacharya, U. Das, and A. Chin, GaAs and Related Compounds 1986, Institute of Physics, London, ed. W. T. Lindley 411-416 (1987).
(20) "An InGaAs/GaAs Multiquantum Well Electro-Absorption Modulator with Integrated Waveguide", U. Das, P. R. Berger, and P. K. Bhattacharya, Optics Lett. 12, 820 (1987).
(21) "Performance Characteristics of InGaAs/GaAs and GaAs/InGaAlAs Coherently Strained Superlattice Photodiodes", U. Das, Y. Zebda, P. K. Bhattacharya, and A. Chin, Appl. Phys. Lett. 51, 1164 (1987).
(22) "Non-Linear Effects in Coplanar GaAs/InGaAs Strained Layer Superlattice Directional Couplers", U. Das Y. Chen, and P. K. Bhattacharya, Appl. Phys. Lett. 51, 1679 (1987).
(23) "Deep Levels in As-Grown and Si-Implanted In0.2Ga0.8As/GaAs Strained Layer Superlattice Optical Guiding Structures", S. Dhar, U. Das and P. K. Bhattacharya, J. Appl. Phys. 60, 639 (1986).
(24) "Low Loss Optical Waveguides made with Molecular Beam Epitaxial In0.012Ga0.988As and In0.2Ga0.8As - GaAs Superlattices", U. Das, P. K. Bhattacharya, and S. Dhar, Appl. Phys. Lett. 48, 1507 (1986).
(25) "Variation of Refractive Index in Strained InxGa1-xAs Heterostructures", U. Das, and P. K. Bhattacharya, J. Appl. Phys. 58, 341 (1985).
(26) "Electron and Hole Impact Ionization Coefficients in GaAs/AlGaAs Superlattices", F-Y. Juang, U. Das, Y. Nashimoto, and P. K. Bhattacharya, Appl. Phys. Lett. 47, 972 (1985).
(27) "Material Properties and Optical Guiding in InGaAs/GaAs Strained Layer Superlattices - A Brief Review", P. K. Bhattacharya, U. Das, F-Y. Juang, Y. Nashimoto and S. Dhar, Solid State Electronics 29, 261 (1985).
(28) "Refractive Indices and Optical Guiding in InxGa1-xAs-GaAs Strained-Layer Superlattices", U. Das, P. K. Bhattacharya, Y. Nashimoto, and F-Y.Juang, GaAs and Related Compounds 1985, Institute of Physics, London, ed. T. Ikoma, 427-432 (1985).
(29) "Transport Properties of n-type Chemical-Vapor-Deposited AlxGa1-xAs (0
Publication Citations :
Four papers cited in Vol. 24 of monogram series on Semiconductors and Semimetals Till May 1995 Journal papers (28) cited 13 times, 24(9 times), 23(7 times), 21(18 times), 19(6 times), 16(10 times), 14 (Once). Average of 3 citations per paper has been received.
Refereed Conference Presentations :
(Published in Proceedings)(1)"40GHz Integrated MQW Intermixed Waveguide Photodiodes", T. Bhowmick and U. Das, Poster No. OP-P.25, IWPSD 2011, Dec. 19-22, 2011, IIT Kanpur, Kanpur, UP, India. [Best Poster Award] . (2)"Growth of SiC Nano-Crystals on H-Terminated Si(100)3o Substrate Surface Steps", D. Jain, C. Sandeep, and U. Das, Poster No. OP-P.27, IWPSD 2011, Dec. 19-22, 2011, IIT Kanpur, Kanpur, UP, India. (3)"Fabrication of Waveguide Grating", S. Sonkar and U. Das, Presentation No. OP-O.04, IWPSD 2011, Dec. 19-22, 2011, IIT Kanpur, Kanpur, UP, India. (4) "Formation of SiC nanostructures on Si surface using C60 by spinning technique", A. Mondal, N. Jadav, and U. Das, Advanced Optoelectronic Materials and Devices (AOMD-2008) Dec. 22-24, 2009 at IT-BHU, Varanasi, India. Proceedings (Print ISBN: 978-0-230-63718-4), pp28-35 (2009).
(5) "85GHz Integrated InGaAsP/InP Multi Quantum Well Intermixed Waveguide Photodiodes", T. Bhowmick and U. Das, NCC 2009, Jan. 16-18, IIT Guwahati, pp.71-74, 2009.
(6) T. Bhowmick and U. Das, "Integrated InGaAsP/InP Multi Quantum Well Waveguide Photodiodes at CWDM Wavelengths", 14th National Conference on Communication, IIT Bombay, India, pp.327-331, 2008.
(7) R. K. Sonkar and U. Das, "Integrated Waveguide Grating Using Impurity Induced Quantum Well Intermixing," in Asia Optical Fiber Communication and Optoelectronic Exposition and Conference, Shanghai, China, Oct. 30-Nov. 02, 2008, OSA Technical Digest (CD) (Optical Society of America, 2008), paper SaK26.
(8) T. Bhowmick and U. Das, "Integrated MQW Intermixed InGaAsP/InP Waveguide Photodiodes", Asia Optical Fiber Communication and Optoelectronic Exposition & Conference (AOE), Shanghai, China, Oct. 30-Nov. 02, 2008, OSA Technical Digest (CD) (Optical Society of America, 2008), paper SAK38.
(9) T. Bhowmick, U. Das, A. Nigam, and A. Singh, "Absorption Profile of Quantum Well Intermixed InGaAsP/InP Waveguide Photodiode Structures", Proceedings of the 3rd International Conference on Computers and Devices for Communication (CODEC-06), Institute of Radio Physics and Electronics, University of Calcutta, pp. 465- 468, Dec. 18-20, 2006.
(10) "Analysis of Implantation Induced Gratings for CWDM", R. K. Sonkar and U. Das, Proc. CLEO/QELS 2005, 904-906, Vol. 2, Baltimore, Maryland, USA.
(11) R. K. Sonkar, A. K. Srivastava and U. Das, "Ion Implanted CWDM Bragg Gratings", XXXI Symposium of the Optical Society of India, ICOL-2005, Dec. 12-15, Dehradun, India, Proceedings pp-158, 2005.
(12) "Microstrip and Suspended Substrate GaAs Bias-T", A. D. Gopalaswamy, and U. Das, Proceedings of the Internationa Conference on Fiber optics and Photonics (PHOTONICS-2000), Dec. 18-20, 2000, Calcutta, India, vol-1, pp291-293.
(13) "Bias-Ts for Optoelectronic Applications", A. D. Gopalaswamy, and U. Das, Proceedings of the International Conference on Communications, Computers, and Devices, IIT Kharagpur, Kharagpur, India, Vol -1, pp320- 322, Dec. 2000.
(14) "Suspended Radial Line Stub", R. K. Joshi, A. Biswas, and U. Das, Proceedings of the International Conference on Communications, Computers, and Devices, IIT Kharagpur, Kharagpur, India, Vol -1, pp309- 312, Dec. 2000.
(15) "Anodic Oxides on GaAs for Photodiode insulation masks", B. Jacob and U. Das, Proceedings of 10th International Workshop on the Physics of Semiconductor Devices, Dec. 14 - 18, 1999, New Delhi, India, pp 149 - 156, Ed. V. Kumar and S. K. Agarwal, Allied Publishers.
(16) "Calculation of reflection efficiency in waveguide DBR by spatially selective disordering of GaAs0.91P0.09/Al0.3Ga0.7As MQWs", B. Jacob and U. Das, Proceedings of IEEE(LEOS) '98 annual meeting, Dec. 1-4, Orlando, FL, USA, IEEE Catalog No. 98CH36243, vol2, pp55-56.
(17) "Refractive index variation in F Impurity Induced Disordered Strained GaAsP/AlGaAs Quantum Wells", B. Jacob and U. Das, pp496-499, Proc. CODEC, Jan 14-17, 1998, Calcutta (Science City), India, Allied Publishers.
(18) "Model for F Induced Disordering of GaAs/InGaP Quantum Wells", K. M. V. B. Saikrishna and U. Das, pp619, Proceedings of the Intl. Conf. on Computers and Devices for Communication(CODEC), Jan 14-17, 1998, Calcutta (Science City), India.
(19) "Spatial Dependence of Fluorescence in Human Breast Tissues", N. Ghosh, B. V. Laxmi, U. Das, A. Agarwal, and A. Pradhan, Proceedings of the National Laser Symposium, Ahmedabad (India), Dec 10-12 (1997), pp288.
(20) "Micro-Raman Characterization of GaAs/Si with Atomic Layer Epitaxy grown Predeposition layer", P. S. Dobal, A. Pradhan, and U. Das, pp301-303, Proceedings of 9th International Conference on Physics of Semiconductor Devices, Dec. 16-20, 1998, Eds. V. Kumar and S. K. Agarwal, Narosa Publishing House, New Delhi, India.
(21) "Fluorine impurity induced layer disordered AlGaAs/GaAsP strained Quantum wells : Experiment and Model", U. Das, pp228-235, Proceedings of 9th International Conference on Physics of Semiconductor Devices, Dec. 16-20, 1998, Eds. V. Kumar and S. K. Agarwal, Narosa Publishing House, New Delhi, India.
(22) "Atomic Layer Epitaxial Predeposition for GaAs/Si", U. Das, S. Dhar, and M. Mazumdar, presented at the 'National Conference on Recent Advances in Semiconductors' June 20 - 22, 1995, IIT Delhi. (Proceedings yet not received)
(23) "Nonlinearities in Strained (111)B InxGa1-xAs/Al0.2Ga0.8As Multiple Quantum Wells", U. Das, Z. Osman, and A. Chin, presented at the 'National Conference on Recent Advances in Semiconductors' June 20 - 22, 1995, IIT Delhi. (Proceedings not received yet.)
(24) "Fluorine Induced Group V Inter-diffusion in III-V Quantum Wells", U. Das, presented at the 'National Conference on Recent Advances in Semiconductors' June 20 - 22, 1995, IIT Delhi. (Proceedings not received yet)
(25) "Photoluminescence Spectroscopy of (111)B III-V semiconductors ------- Peculiarities and Applications", U. Das, Workshop on Advanced Laser Spectroscopy, Feb. 25 - 28 (1995), IIT Kanpur, Kanpur 208016, India. (Proceedings by Allied Publishers)
(26) "Proposal for an integrated Photo diode-HBT amplifier using impurity induced layer disordering of QWs", U. Das, International Conference on Emerging Optoelectronic Technologies, July 18-22 (1994), Bangalore, India. (Not included in proceedings for late acceptance)
(27) "Selective Area Growth of InGaAsP on InP Substrates for Optical Waveguide Applications", B. Pathangey, Z. Osman, U. Das, and T. J. Anderson, Presented at the MOCVD conference, Panama City, FL, USA.
(28) "Selective area growth of GaInAsP on InP by MOVPE", Z. Osman, B. Pathangey, U. Das, and T. J. Anderson, presented at the 183rd meeting of the Electrochemical Soc. Inc., May 16-21, 1993, Honolulu, Hawaii, USA.
(29) "Tapered Waveguide Interconnect by Zinc Diffusion Induced Layer Disordering of Quantum Wells", S. Sinha, R. V. Ramaswamy, X. Cao, and U. Das, Integrated Optoelectronics Conference (IEEE/LEOS), Aug 5-7 1992, Santa Barbara, CA, USA.
(30) "Low Pressure MOVPE Growth of GaInP/GaAs Heterojunctions: Growth Interruption Studies Using EDMI and TEG", K. C. Chou, H. D. Lee, B. Pathangey, T. J. Anderson, Z. Osman, U. Das, J. E. Yu, and K. Jones, presented at the Electro-chem. Soc. Inc. Electronic/dielectric Sc. and Tech. State Of The Art Program On Compound Semiconductors Conf. (SOTAPOCS) XVI, May 18-22, 1992, St. Louis, Missouri, USA.
(31) "Selective Area Metalorganic Vapor Phase Epitaxy of GaInAsP on InP", Z. Osman, B. Pathangey, U. Das, and T. J. Anderson, presented at the 2nd international meeting of APCT 1991, Clearwater Beach, Florida, USA (AIP Conf. Proc. No. 227, AVS series 10).
(32) "Tailoring of electron and hole energies in strained GaAsP/AlGaAs quantum wells using impurity induced layer disordering", U. Das, S. Davis, J-T. Hsu, R. V. Ramaswamy, and F. A. Stevie, presented at the 2nd International meeting of APCT 1991, Clearwater Beach, Florida, USA (AIP Conf. Proc. No. 227, AVS series 10).
(33) "III-V Superlattice Photodiodes", F-Y. Juang, W. Li, P. K. Bhattacharya, U. Das, A. Chin, D. J. Jackson, and D. L. Persechini, 13th Int'l Symposium on GaAs and Related Compounds, September (1986), Las Vegas, Nevada, USA.
(34) "Refractive Indices and Optical Guiding in InGaAs/GaAs Strained Layer Superlattices", U. Das, Y. Nashimoto, F-Y. Juang, and P. K. Bhattacharya, 12th Int'l Symposium on GaAs and Related Compounds, September (1985), Karuizawa, Japan.
(35) "GaAs/AlGaAs Superlattice Avalanche Photo diode: Ionization Coefficients and Performance Characteristics", F-Y. Juang, U. Das, Y. Nashimoto, and P. K. Bhattacharya, 10th Biennial IEEE/Cornell Conf. on High Speed Semiconductor Devices and Circuits, August (1985), Ithaca, New York, USA.
Refereed Conference Presentations :
(Only Abstracted)(1) T. Bhowmick and U. Das, "85GHz Integrated MQW Intermixed Waveguide Photodiodes", Photonics 2009, IIT Delhi, India, Dec. 2009. Poster not presented because none could visit.
(2) T. Bhowmick and U. Das, "85GHz Integrated InGaAsP/InP Multi Quantum Well Intermixed Waveguide Photodiodes", Proceedings of the 4th International Conference on Computers and Devices for Communication (CODEC-09), Inst. of Radio Physics and Electronics, Univ. of Calcutta, Dec. 2009. Accepted but could not attend.
(3) "CWDM Bragg Gratings using F-Implanted QW Intermixing", R. K Sonkar, A. K Srivastava and U. Das, EPDMS '06, Calcutta, India. (Not in Proceedings because of late submission)
(4) "Analysis of CWDM grating", R. K. Sonkar and U. Das, Photonics 2004,7th Intl. Conf. on Optoelectr., Fiber Optics and Photonics, December 9-11 2004, Cochin, India.
(5) "Analysis of Implantation Induced Bragg Gratings in Quantum Wells", R. K. Sonkar and U. Das, pp - Proceedings of CODEC - 04, Jan. 01-03, 2004, Kolkata, Imdia.
(6) "Impurity Induced Disordering of Quantum Wells and Applications", U. Das and G. S. Prasad, Conference on Horizons of Telecommunications, Feb. 3-5, 2003, Kolkata, Digest p105.
(7) "Broad side Offset coupled suspended substrate radial line stub", R. C. Mandal and U. Das, accepted for presentation at Symposium on Advances in microwave, Millimeter wave and Infrared Technology, Dec. 21 - 24, 1999. Calcutta, India. . [Finally not presented as acceptance of paper arrived on Dec. 22, 1999.]