An International Research Journal

AJP

SSN : 0971 - 3093

Vol 27, No 2, February, 2018

Asian Journal of Physics                                                                                                                Vol. 27 No 2, (2018), 87-91


On the occasion of 90th Anniversary of Discovery of Raman Effect

Reproduced from Asian J Phys, Vol 7,No 2, April-June, 1998,175-178


C V Raman : The Aesthete Physicist


G  L  Gautam ‘Prabhat’
L R College, Sahibabad-20 1 005, India


                Chandrasekhara Venkata Raman—the living legend of science of 20th century–breathed science until he breathed his last in 1970. The other distinguished name that comes to my mind while writing about Raman is that of Gurudev Rabindra Nath Tagore whose heart beat for artistic pursuits all his life till his death in 1941. Although Tagore was born in 1861, 26 years earlier than Raman’s birth in 1888, both of them lived into the 20th century when India was struggling against foreign domination and their world-astounding achievements buoyed and rejuvenated imperially suppressed India. The coveted honour, two Nobel Prizes, these representatives of Indian mind brought home infused fresh vitality and vigour into down-hearted Indian people fighting the battle for freedom. The international honour was conferred upon Tagore (Fig 1) in 1913, and then when in 1930 the second honour came, the whole of India watched on Raman (Fig 2) with bated breath, the wonder at Raman’s achievement gave place to belief in prowess of Indian mind and Raman emerged as an internationally known physicist immediately after the discovery of the wonderful phenomena in the study of scattering of light. The honour deservedly bestowed upon Raman brought India in forefront of the commune of nations that prided upon their scientific achievements. The life story of this legend of science reads rather like fiction than real.

C V Raman-The Aesthete Physicist.pdf
G L Gautam ‘Prabhat’

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Asian Journal of Physics                                                                                                                Vol. 27 No 2, (2018), 93-101


On the Occasion of 90th Anniversary of the Raman Effect

Rajinder Singh1 and V K Rastogi2,3
1Research Group: Physics Education and History of Science.
Physics Department, Institute of Physics. University of Oldenburg.26111 Oldenburg, Germany
2R D Foundation Group of Institutions, Kadrabad (Modinagar), Ghaziabad, India
3Indian Spectroscopy Society , KC-68/1, Old Kavinagar, Ghaziabad-201 002, India


On February 28, 1928, at the Indian Association for the Cultivation of Sciences, Kolkata (IACS), C V Raman and his associates showed that when monochromatic light is scattered by transparent media, the scattered light contains not only the original colour, but also other colours. This effect was named as Raman effect. In 1930, for the discovery of the Raman effect and work done on light scattering Raman received the Nobel Prize: the greatest award in the whole world. On the occasion of the 90th anniversary of the Raman effect, a brief  overview about the discovery and its reception by the scientific community is given here.

The first three decades of the 20th century are considered as the “Golden Period” of “Indian Physics”. The well-known facts are: In the beginning of the 1920s; M N Saha gave the Saha ionisation (also known as Saha-Eckert Equation), which explained the structure of stars [1]. On June 4, 1924, S N Bose wrote a letter to Albert Einstein, in which he stated that he (Bose) has derived Planck radiation law by applying his (Einstein’s) quantum nature of light. Einstein translated Bose’s manuscript, which was published in the German journal “Zeitschrift für Physik” [2]. Einstein further developed Bose’s idea. Consequently Bose-Einstein emerged [3]. In 1928 C V Raman, K S Krishnan and S Venkateswaran (Fig 1) discovered the Raman effect. 
Total Refs: 32

On the Occasion of 90th Anniversary of the Raman Effect.pdf
Rajinder Singh and V K Rastogi

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Asian Journal of Physics                                                                                                                Vol. 27 No 2, (2018), 103-136


A brief overview on robust nonlinear optical (NLO) crystals KDP
and ADP and their doped systems


M J Joshi

Crystal Growth Laboratory, Department of Physics, Saurashtra University

Rajkot-360 005, Gujarat, India

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Potassium dihydrogen phosphate (KDP) and ammonium dihydrogen phosphate (ADP) crystals are well known for their nonlinear optical (NLO) properties. KDP (KH2PO4) and ADP (NH4H2PO4) crystals are widely used in frequency doubling,  tripling and  quadrupling of Nd-doped laser systems, as well as in the electro-optical modulators. Inspite of having developed myriad varieties of new NLO materials, due to robust and well proven reliable nature with excellent nonlinear optical parameters and high laser damage threshold values, the KDP and ADP systems are still remain at cynosure of researchers and technologists and can be popularly labeled as “old is gold”. Both the crystals possess tetragonal structure. To engineer and modify their properties, different dopants are used ranging from different cations to amino acids and nano-particles. In the present overview, the growth, characterization and importance of KDP and ADP crystals and their doped systems are described. The important results and landmarks achieved by the scientific community on these NLO crystals  in  recent years have been covered. © Anita Publications. All rights reserved.

Total Refs : 252

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Asian Journal of Physics                                                                                                                Vol. 27 No 2, (2018), 137-142


Raman spectroscopy in oral cancers: insights from animal studies


Piyush Kumar1*, A Ingle2, and C Murali Krishna2

1Amity Institute of Biotechnology, Amity University Mumbai, Panvel- 410 206, India

2TMC-ACTREC, Kharghar, Navi Mumbai, 410210 and HBNI, Anushakti Nagar, Mumbai 400 094,India

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Oral cancers are a major health burden in South Asian nations primarily due to late detection. Raman spectroscopy (RS), being sensitive to tissue biochemistry, can be a potential diagnostic tool, especially in cancers, as biochemical changes precede morphological alterations during carcinogenesis. RS has been employed to explore oral cancers in both human subjects and animal models. Hamster buccal pouch model is widely employed for experimental carcinogenesis. The present article discusses insights obtained from RS based studies on the hamster models for oral cancers.© Anita Publications. All rights reserved.

Total Refs : 53

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Asian Journal of Physics                                                                                                                Vol. 27 No 2, (2018), 143-152


Growth, structural, dielectric, photoluminescence and Z-scan analysis of
L-methioninium picrate (LMP) single crystals


A Alexandara,b, S Sakthy Priyaa, K Balakrishnana, P Surendrana, A Lakshmanana and P Rameshkumara,

aPG and Research Department of Physics, Periyar E.V.R. College (Autonomous), Tiruchirappalli-620023, India,

bDepartment of Mathematics, Anugraha Institute of Social Sciences, Dindigul-624003, India

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Organic nonlinear optical (NLO) single crystal of L-methioninium picrate (LMP) has been grown by solution growth technique and subjected to various characterization techniques. The crystal data were obtained using single crystal X-ray diffractometer analysis. The molecular structure and crystal-packing diagram of LMP were plotted using Mercury Software. The morphology of the crystal was drawn using WinXMorph software package. Dielectric constant and dielectric loss as a function of frequency and temperature were measured. Luminescence behavior of the material was examined using photoluminescence spectrum at three different wavelengths. Third order nonlinear optical properties of the grown crystal were analyzed by open aperture and closed aperture Z-scan analysis using He-Ne laser also for the first time. © Anita Publications. All rights reserved.

Keywords: Solution growth, Single crystal, Dielectric constant, Photoluminescence; NLO behaviour

Total Refs : 15

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© ANITA PUBLICATIONS

All rights reserved