C. V. Raman
Sir Chandrasekhara Venkata Raman,
FRS was an Indian physicist whose work was influential in the growth of science
in India.
Education: Presidency College, Chennai (1907), Presidency College, Chennai (1902–1904), University of Madras
Sir Chandrasekhara Venkata Raman, FRS (7 November 1888 – 21
November 1970) was an Indian physicist whose work was influential in the growth
of science in India. He was the recipient of the Nobel Prize for Physics in 1930 for the discovery that when light traverses a
transparent material, some of the deflected light changes in wavelength. This
phenomenon is now called Raman
scattering and is the result of the Raman
effect.
Venkata Raman was born in Thiruvanaikaval, Trichinopoly, Madras
Province, in British
India to R. Chandrasekhara Iyer (b. 1866) and Parvati Ammal
(Saptarshi Parvati).He was the second of their five children. At an early age,
Raman moved to the city of Visakhapatnam, Andhra Pradesh, and studied in St. Aloysius Anglo-Indian
High School. His father was a lecturer in mathematics and physics at Presidency College in Madras, which Raman entered in 1902 at the age of 13 In
1904 he passed his B.A. examination in first place and won the gold medal in
physics, and in 1907 he gained his M.A. degree with the highest distinctions.
In 1917,
Raman resigned from his government service after he was appointed the
first Palit Professor of
Physics at the University of
Calcutta. At the same time, he continued
doing research at the Indian Association for the Cultivation of Science (IACS), Calcutta, where he became the
Honorary Secretary. Raman used to refer to this period as the golden era of his
career. Many students gathered around him at the IACS and the University of
Calcutta.
On 28
February 1928, Raman led experiments at the IACS with collaborators,
including K. S. Krishnan, on the scattering of
light, when he discovered the Raman effect. A
detailed account of this period is reported in the biography by G.
Venkatraman. It was instantly clear that this discovery was of huge value.
It gave further proof of the quantum nature of light.
Raman spectroscopy came to be based on this phenomenon,
and Ernest Rutherford referred to it in his presidential address to
the Royal Society in 1929. Raman was president of the 16th
session of the Indian Science
Congress in 1929. He was conferred
a knighthood, and
medals and honorary doctorates by various universities. Raman was confident of
winning the Nobel Prize in
Physics as well, but was
disappointed when the Nobel Prize went to Richardson in
1928 and to de Broglie in 1929. He did eventually win the 1930 Nobel Prize in
Physics "for his work on the
scattering of light and for the discovery of the Raman effect".
He was the first Asian and first non-White to receive any Nobel Prize in the
sciences. Before him Rabindranath Tagore (also Indian) had received the Nobel Prize
for Literature in 1913.
Raman
and Bhagavantam discovered the quantum photon spin in 1932,
which further confirmed the quantum nature of light.
During
his tenure at IISc, he recruited the then talented electrical engineering
student, G. N. Ramachandran, who later was a distinguished X-ray
crystallographer himself.
Raman
also worked on the acoustics of
musical instruments. He worked out the theory of transverse vibration
of bowed strings, on the basis of superposition velocities. He was also the first to
investigate the harmonic nature of the sound of the Indian drums such as tabala and
the mridangam.
Raman and
his student, Nagendra Nath, provided the correct theoretical explanation for
the acousto-optic effect (light scattering by sound waves), in a series of
articles resulting in the celebrated Raman-Nath theory. Modulators, and
switching systems based on this effect have enabled optical communication
components based on laser systems.
Raman was
succeeded by Debendra Mohan Bose as the Palit Professor in 1932. In 1933,
Raman left IACS to join Indian Institute of
Science in Bangalore as
its first Indian director. Other investigations carried out by Raman were
experimental and theoretical studies on the diffraction of light by acoustic
waves of ultrasonic and
hypersonic frequencies (published 1934–1942), and those on the effects produced
by X-rays on infrared vibrations in crystals exposed to ordinary light.
He also
started a company called Travancore Chemical and Manufacturing Co. Ltd. in 1943
along with Dr. Krishnamurthy. The Company during its sixty year history
established four factories in Southern India. In 1947, he was appointed as the
first National Professor by the new government of Independent India.
In 1948,
Raman, through studying the spectroscopic behaviour of crystals, approached in
a new manner fundamental problems of crystal dynamics. He dealt with the
structure and properties of diamond, the structure and optical behaviour of
numerous iridescent substances
(labradorite,
pearly feldspar, agate, opal, and pearls). Among his other interests were the optics
of colloids,
electrical and magnetic anisotropy, and the
physiology of human vision.
Personal life
He was
married on 6 May 1907 to Lokasundari Ammal (1892–1980) with whom he had two
sons, Chandrasekhar and Radhakrishnan.
On his religious
views, he was said to be an agnostic.
Raman
retired from the Indian Institute of
Science in 1944 and established
the Raman Research
Institute in Bangalore,
Karnataka a year later. He served as its director and remained active there
until his death in 1970, in Bangalore, at the age of 82
Raman was
the paternal uncle of Subrahmanyan
Chandrasekhar, who
later won the Nobel Prize in
Physics (1983) for his discovery of
the Chandrasekhar limit in 1931 and for his subsequent work on the
nuclear reactions necessary for stellar evolution.
Honours and awards
Raman was
honoured with a large number of honorary doctorates and memberships of
scientific societies.
·
He was
awarded the Lenin Peace Prize in 1957. In 1998, the American Chemical
Society and Indian Association for the Cultivation of Science recognised Raman's discovery as an International
Historic Chemical Landmark.
India
celebrates National Science Day on 28 February of every year to commemorate
the discovery of the Raman Effect in 1928.
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