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- Anil Kumar
- Harish Kumar
- Shakti Singh
- Girija Moona
- Satish
- P. K. Dubey
- H. K. Singh
- Goutam Mandal
- D. K. Aswal
- Manju Singh
- Rishu Chaujar
- Sudhir Husale
- S. Grover
- Amit P. Shah
- Mandar M. Deshmukh
- Anurag Gupta
- V. N. Singh
- R. K. Rakshit
- Lakhi Sharma
- S. De
- P. Kandpal
- M. P. Olaniya
- S. Yadav
- T. Bhardwaj
- P. Thorat
- S. Panja
- P. Arora
- N. Sharma
- A. Agarwal
- T. D. Senguttuvan
- Rajesh
- V. K. Tanwar
- G. Sumana
- V. V. Agarwal
- Saood Ahmad
- Anish M. Bhargav
Journals
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Ojha, V. N.
- National Physical Laboratory Demonstrates 1 G Kibble Balance:Linkage of Macroscopic Mass to Planck Constant
Abstract Views :276 |
PDF Views:78
Authors
Anil Kumar
1,
Harish Kumar
1,
V. N. Ojha
1,
Shakti Singh
2,
Girija Moona
1,
Satish
1,
P. K. Dubey
1,
H. K. Singh
1,
Goutam Mandal
1,
D. K. Aswal
1
Affiliations
1 CSIR-National Physical Laboratory, New Delhi 110 012, IN
2 Amity University, Gurugram 122 413, IN
1 CSIR-National Physical Laboratory, New Delhi 110 012, IN
2 Amity University, Gurugram 122 413, IN
Source
Current Science, Vol 113, No 03 (2017), Pagination: 381-382Abstract
Mass is the only base unit, which is represented as a primary standard in the form of artifact for more than 125 years. International prototype of kilogram (IPK) is kept at the Bureau International des Poids et Mesures (BIPM), Paris and serves as the international standard of kilogram. It is made of 90% platinum and 10% iridium and as a cylinder of 39 mm diameter and 39 mm height. Replicas of the IPK are made of the same material and used at BIPM as reference or working standards and national prototype of kilogram (NPK), kept at different National Metrology Institutes (NMIs). NPK-57, kept at CSIR-National Physical Laboratory, is sent periodically to BIPM for calibration.Full Text
References
- Davis, R., Metrologia, 2003, 40, 299–305.
- Stock, M., Barat, P., Davis, R. S., Picard, A. and Milton, M. J. T., Metrologia, 2015, 52, 310–336.
- Kibble, B. P. and Robinson, I. A., Feasibility study for a moving coil apparatus to relate the electrical and mechanical SI units. Technical Report DES 40, NPL, 1977.
- Kibble, B. P., Robinson, I. A. and Belliss, J. H., Metrologia, 1990, 27, 173–192.
- Haddad, D. et al., Rev. Sci. Instrum., 2016, 87, 061301.
- Influence of Fabrication Processes on Transport Properties of Superconducting Niobium Nitride Nanowires
Abstract Views :319 |
PDF Views:89
Authors
Manju Singh
1,
Rishu Chaujar
2,
Sudhir Husale
1,
S. Grover
3,
Amit P. Shah
3,
Mandar M. Deshmukh
3,
Anurag Gupta
1,
V. N. Singh
1,
V. N. Ojha
1,
D. K. Aswal
1,
R. K. Rakshit
1
Affiliations
1 Academy of Scientific and Innovative Research, CSIR-NPL Campus, Dr K.S. Krishnan Marg, New Delhi 110 012, IN
2 Microelectronics Research Laboratory, Department of Engineering Physics, Delhi Technological University, Bawana Road, Delhi 110 042, IN
3 Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, IN
1 Academy of Scientific and Innovative Research, CSIR-NPL Campus, Dr K.S. Krishnan Marg, New Delhi 110 012, IN
2 Microelectronics Research Laboratory, Department of Engineering Physics, Delhi Technological University, Bawana Road, Delhi 110 042, IN
3 Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, IN
Source
Current Science, Vol 114, No 07 (2018), Pagination: 1443-1450Abstract
Fabrication of niobium nitride (NbN) superconducting nanowires based on focused ion beam (FIB) milling and electron beam lithography (EBL) is presented. The NbN films were deposited using reactive magnetron sputtering. Argon-to-nitrogen ratio turned out to be a crucial factor in synthesizing high quality superconducting NbN. Critical temperatures (Tc) of around 15.5 K were measured for films with a thickness of around 10 nm. Zero-field-cooled magnetization was measured to optimize the superconducting properties of ultra thin NbN films. The transport behaviour was studied using conventional resistance vs temperature and current-voltage characteristics down to 2 K. Effect of gallium contamination on superconducting properties has been discussed. Whereas the various processing steps of standard EBL route do not have any significant impact on the superconducting transition temperature as well as on the transition width of nanowires, there is significant degradation of superconducting properties of nanowires prepared using FIB. This has been attributed to gallium ion implantation across the superconducting channel. Although the effect of gallium implantation may have technological limitations in designing fascinating single photon detector architectures, it provides some interesting low-dimensional superconducting properties.Keywords
DC Magnetron Sputtering, EBL, FIB, Niobium Nitride, Superconducting Nanostructure, Thin Films.Full Text
References
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- Takesue, H., Nam, S. W., Zhang, Q., Hadfield, R. H., Honjo, T., Tamaki, K. and Yamamoto, Y., Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors. Nat. Photon., 2007, 1, 343–348.
- Hadfield, R. H., Single-photon detectors for optical quantum information applications. Nat. Photon., 2009, 3, 696–705 and references therein.
- Rosenberg, D. et al., Practical long-distance quantum key distribution system using decoy levels. New J. Phys., 2009, 11, 045009(1–10).
- Stucki, D. et al., High rate, long-distance quantum key distribution over 250 km of ultra low loss fibres. New J. Phys., 2009, 11, 075003(1–9).
- Liu, Y. et al., Decoy-state quantum key distribution with polarized photons over 200 km. Opt. Express, 2010, 18, 8587–8594.
- Eisaman, M. D., Fan, J., Migdal, A. and Polyakov, S. V., Invited review article: single-photon sources and detectors. Rev. Sci. Instrum., 2011, 82, 071101(1–25) and references therein.
- Natarajan, C. M., Tanner, M. G. and Hadfield, R. H., Superconducting nanowire single-photon detectors: physics and applications. Supercond. Sci. Tech., 2012, 25, 063001(1–16) and references therein.
- Wang, S. et al., 2 GHz clock quantum key distribution over 260 km of standard telecom fiber. Opt. Lett., 2012, 37, 1008–1010.
- Yao, X.-C. et al., Experimental demonstration of topological error correction. Nature, 2012, 482, 489–494.
- Ma, X.-S. et al., Quantum teleportation over 143 kilometres using active feed-forward. Nature, 2012, 489, 269–273.
- Pan, J.-W., Chen, Z.-B., Lu, C.-Y., Weinfurter, H., Zeilinger, A. and Zukowski, M., Multiphoton entanglement and interferometry. Rev. Mod. Phys., 2012, 84, 777–838.
- Shimizu, K. et al., Performance of long-distance quantum key distribution over 90-km optical links installed in a field environment of Tokyo metropolitan area. J. Lightwave Technol., 2014, 32, 141–151.
- Northup, T. E. and Blatt, R., Quantum information transfer using photons. Nat. Photon., 2014, 8, 356–363.
- Korzh, B. et al., Provably secure and practical quantum key distribution over 307 km of optical fibre. Nat. Photon., 2014, 9, 163–168.
- Takesue, H., Dyer, S. D., Stevens, M. J., Verma, V., Mirin, R. P. and Nam, S. W., Quantum teleportation over 100 km of fiber using highly efficient superconducting nanowire single-photon detectors. Optica, 2015, 2, 832–835.
- Engel, A., Renema, J. J., Il’in, K. and Semenov, A., Detection mechanism of superconducting nanowire single-photon detectors. Supercond. Sci. Tech., 2015, 28, 114003(1–22) and references therein.
- Chunnilall, C. J., Degiovanni, I. P., Kuck, S., Muller, I. and Sinclair, A. G., Metrology of single-photon sources and detectors: a review. Opt. Eng., 2014, 53, 081910(1–17).
- Lita, A. E., Miller, A. J. and Nam, S. W., Counting near-infrared single-photons with 95% efficiency. Opt. Express, 2008, 16, 3032–3040.
- Miki, S. et al., Large sensitive-area NbN nanowire superconducting single-photon detectors fabricated on single-crystal MgO substrates. Appl. Phys. Lett., 2008, 92, 061116(1–3).
- Korneev, A. et al., Recent nanowire superconducting single-photon detector optimization for practical applications. IEEE Trans. Appl. Supercond., 2013, 23, 2201204(1–4).
- Bergeal, N., Grison, X., Lesueur, J., Faini, G., Aprili, M. and Contour, J.-P., High Tc superconducting quantum interference devices made by ion irradiation. Appl. Phys. Lett., 2006, 89, 112515(1–3).
- Delacour, C. et al., Superconducting single photon detectors made by local oxidation with an atomic force microscope. Appl. Phys. Lett., 2007, 90, 191116(1–3).
- Lee, S.-G., Oh, S., Kang, C. S. and Kim, S.-J., Superconducting nanobridge made from YBa2Cu3O7 film by using focused ion beam. Phys. C Supercond., 2007, 460, 1468–1469.
- Curtz, N., Koller, E., Zbinden, H., Decroux, M., Antognazza, L., Fischer, Ø. and Gisin, N., Patterning of ultrathin YBCO nanowires using a new focused-ion-beam process. Supercond. Sci. Technol. 2010, 23, 045015(1–6).
- Zhang, C. et al., Fabrication of superconducting nanowires from ultrathin MgB2 films via focused ion beam milling. AIP Adv., 2015, 5, 027139(1–8).
- Bachar, G., Baskin, I., Shtempluck, O. and Buks, E., Superconducting nanowire single photon detectors on-fiber. Appl. Phys. Lett., 2012, 101, 262601(1–3).
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- Lehrer, C., Frey, L., Petersen, S., Mizutani, M., Takai, M. and Ryssel, H., Defects and gallium-contamination during focused ion beam micro machining. In Proceedings of IEEE Ion Implantation Technology, 2000, pp. 695–698.
- Mayer, J., Giannuzzi, L. A., Kamino, T. and Michael, J., TEM sample preparation and FIB induced damage. MRS Bull., 2007, 32, 400–407.
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- Ziegler, M., Fritzsch, L., Day, J., Linzen, S., Anders, S., Toussaint, J. and Meyer, H.-G., Superconducting niobium nitride thin films deposited by metal organic plasma-enhanced atomic layer deposition. Supercond. Sci. Technol., 2013, 26, 025008(1–5).
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- Litombe, N. E., Bollinger, A. T., Hoffman, J. E. and Bozovic, I., La2–xSrxCuO4 superconductor nanowire devices. Phys. C Supercond., 2014, 506, 169–173.
- Elmurodov, A. K. et al., Phase-slip phenomena in NbN superconducting nanowires with leads. Phys. Rev. B Condens. Matter, 2008, 78, 214519(1–5).
- Delacour, C., Pannetier, B., Villegier, J.-C. and Bouchiat, V., Quantum and thermal phase slips in superconducting niobium nitride (NbN) ultrathin crystalline nanowire: application to single photon detection. Nano Lett., 2012, 12, 3501–3506.
- Necessity of ‘Two Time Zones: IST-I (UTC + 5 : 30 h) and IST-II (UTC + 6 : 30 h)’ in India and Its Implementation
Abstract Views :222 |
PDF Views:75
Authors
Lakhi Sharma
1,
S. De
1,
P. Kandpal
2,
M. P. Olaniya
2,
S. Yadav
2,
T. Bhardwaj
2,
P. Thorat
2,
S. Panja
1,
P. Arora
1,
N. Sharma
2,
A. Agarwal
1,
T. D. Senguttuvan
1,
V. N. Ojha
1,
D. K. Aswal
1
Affiliations
1 Academy of Scientific and Innovative Research (AcSIR), CSIR-NPL Campus, New Delhi 110 012, IN
2 CSIR-National Physical Laboratory (CSIR-NPL), Dr K. S. Krishnan Marg, New Delhi 110 012,, IN
1 Academy of Scientific and Innovative Research (AcSIR), CSIR-NPL Campus, New Delhi 110 012, IN
2 CSIR-National Physical Laboratory (CSIR-NPL), Dr K. S. Krishnan Marg, New Delhi 110 012,, IN
Source
Current Science, Vol 115, No 7 (2018), Pagination: 1252-1261Abstract
A strong demand of a separate time zone by northeast populace has been a matter of great debate for a very long period. However, no implementable solution to this genuine problem has yet been proposed. The CSIR-National Physical Laboratory, CSIR-NPL (the National Measurement Institute, NMI, o f India and custodian o f Indian Standard Time, IST) proposes an implementable solution that puts the country in two time zones: (i) IST-I (UTC + 5: 30 h, represented by longitude passing through 82 °33 E) covering the regions falling between longitude 68 °7 E and 89 °52 E and (ii) IST-II (UTC + 6: 30 h, represented by longitude passing through 97°30E) encompassing the regions between 89°52E and 97°25E. The proposed demarcation line between IST-I and IST-II, falling at longitude 89 °52 E, is derived from analyses o f synchronizing the circadian clocks to normal office hours (9: 00 a.m. to 5 : 30p.m.). This demarcation line passes through the border of West Bengal and Assam and has a narrow spatial extension, which makes it easier to implement from the railways point o f view. Once approved, the implementation would require establishment of a laboratory for ‘Primary Time Ensemble - I I ’ generating IST-II in any o f the north-eastern states, which would be equivalent to the existing ‘Primary Time Ensemble-I’ at CSIR-NPL, New Delhi.Keywords
Circadian Clock, Energy Saving, Indian Standard Time, Longitude, Sun Graphs, Two Time Zone.Full Text
References
- Liang, L., One India, two time zones. The Hindu, 2017; retrieved from http://www.thehindu.com/opinion/op-ed/one-india-two-timezones/article17653169.ece
- Wikimedia Commons, Standard time zones of the world. Retrieved from https://commons.wikimedia.org/wiki/File:Standard time zones of the world (2012).svg
- Bureau International des PoidsetMesures (BIPM), Coordinate Universal Time, UTC, retrieved from https://www.bipm.org/cc/CCTF/Allowed/18/CCTF 09-32 noteUTC.pdf
- Bureau International des Poidset Mesures (BIPM), SI Brochure: The International System of Units (SI), Unit of time (second), retrieved from https://www.bipm.org/en/publications/si-brochure/ second.html
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- Bureau International des Poidset Mesures (BIPM), Member States and Associates of the Metre Convention, retrieved from www.bipm.org/en/convention/member_states/
- Time and date. com, Time Zones in the United States. Retrieved from https://www.timeanddate.com/time/zone/usa
- National Institute of Standard and Technology, Time and Frequency Services; https://www.nist.gov/pml/time-and-frequency-division/time-services
- United States Naval Oceanography, precise time, retrieved from http://www.usno.navy.mil/USNO/time
- CSIR-National Physical Laboratory, National Measurement Institute of India, Time and Frequency Metrology, retrieved from http://www.nplindia.in/time-and-frequency-metrology-section
- CSIR-National Physical Laboratory, National Measurement Institute of India, CSIR-NPL and ISRO sign MoU for time and frequency traceability services, retrieved from http://www.nplindia.in/csir-npl-and-isro-sign-mou-time-and-frequency-traceability-services.
- Ahuja, D. R., Sen Gupta, D. P. and Agrawal, V. K., Energy savings from advancing the Indian Standard Time by half an hour. Curr. Sci., 2007, 93, 298-302.
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- CSIR-NPL Establishes an Apex-Level Calibration Facility for Defibrillator Analyzer and Defibrillator Machine
Abstract Views :269 |
PDF Views:79
Authors
Affiliations
1 CSIR-National Physical Laboratory, Dr K. S. Krishnan Road, New Delhi 110 012, IN
1 CSIR-National Physical Laboratory, Dr K. S. Krishnan Road, New Delhi 110 012, IN
Source
Current Science, Vol 117, No 2 (2019), Pagination: 179-180Abstract
The ‘New Medical Device Rule 2017’ emphasizes the need of establishing Test and Calibration centres, as notified by the Government of India, for medical device calibration to provide quality control regulation in the health sectors1.Full Text
References
- The Gazette of India, Extraordinary, Part II, section 3, sub-section (i), Registration No. D. L. 33004/99, notified on 31 January 2017.
- Calibrated Phasor Measurement Unit as a Reliable Metrological Tool for National Power Grid Operation in India
Abstract Views :259 |
PDF Views:90
Authors
Affiliations
1 Indian Standard Time Division, CSIR-National Physical Laboratory, New Delhi 110 012, IN
1 Indian Standard Time Division, CSIR-National Physical Laboratory, New Delhi 110 012, IN
Source
Current Science, Vol 121, No 2 (2021), Pagination: 248-254Abstract
At the national power grid in India, stability is one of the most important factors due to disturbances caused by distributed load and time-variant sources. Presently, for monitoring the transmission efficiency and performance of power grids, phasor measurement units (PMUs) are being installed at various locations in the country. Time synchronization, using Coordinated Universal Time (UTC), makes PMU an important and reliable data acquisition equipment across the grids. To ensure reliability and accuracy of the acquired data, PMUs must be calibrated. However, recent development of automated PMU calibrator system by NIST and M/s Fluke, USA has revolutionized the calibration process by enhancing the accuracy and consistency of PMU measurements. The CSIR-NPL PMU system is fully operational to calibrate PMUs according to the IEEE synchrophasor standards. The time consumed to perform the PMU calibration is comparatively much less than the conventional method. A traceable PMU calibrator system has great potential in calibrating PMUs used to monitor, control and protect the power grid.Keywords
Calibration, National Power Grid, Phasor Measurement Unit, Synchrophasor, Time Synchronization, Uncertainty.Full Text
References
- North American Synchrophasor Initiative; http://www.naspi.org
- Zhang, P., Phasor Measurement Unit (PMU) Implementation and Applications, EPRI Report No. 1015511, Electric Power Research Institute, Palo Alto, California, 31 October 2007, p. 2–17; http://www.naspi.org/repository/project_details.aspx?pid=116
- NERC, NERC Real-Time Application of Synchrophasors for Improving Reliability, North American Electric Reliability Council, Princeton, New Jersey, 19 October 2010, p. 77.
- Staffs of the Federal Energy Regulatory Commission and North American Electric Reliability Corporation; Arizona – Southern California Outages on September 8, 2011, Causes and Recommendations, 27 April 2012.
- IEEE Standards Association, Power and Energy Society, Power Systems Relaying Committee, IEEE C37.118.1, Standard for Synchrophasor Measurements for Power Systems.
- IEEE Standards Association, Power and Energy Society, Power Systems Relaying Committee, IEEE C37.242, Guide for Synchronization, Calibration, Testing, and Installation of Phasor Measurement Units (PMU) for Power System Protection and Control.
- IEEE Standard for Synchrophasors for Power Systems. IEEE C37.118-2005.
- IEEE Standard for Synchrophasors Measurement for Power Systems. IEEE C37.118.1-2011.
- IEEE Standard for Synchrophasors Measurement for Power Systems, Amendment 1: Modification of Selected Performance Requirements, IEEE C37.118.1a-2014.
- IEEE Guide for Synchronization, Calibration, Testing, and Installation of Phasor Measurement Units (PMUs) for Power Systems Protection and Control, IEEE C37.242-2013.
- Pirret, R., New standards for test and calibration of phasor measurement units. In NCSL International Workshop and Symposium, Sacramento, California, USA, 2012, pp. 1–12.
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- Narendra, K. et al., Calibration and testing of TESLA phasor measurement unit (PMU) using DOBLE F6150 test instrument, Bulk Power System Dynamics and Control-VII. Revitalizing Operational Reliability. In iREP Symposium, Charleston, SC, USA, 2007, pp. 1–13.
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- Fluke 6135A/PMU Calibration System Operators Manual; http://us.flukecal.com/products/electrical-calibration/electrical-calibrators/6135-apmucal-phasor- measurement-unit-calibration
- Tang, Y. and Stenbakken, G. N., Traceability of calibration for phasor measurement unit. In Power and Energy Society General Meeting, San Diego, California, USA, 2012, pp. 1–5.