Sir Chandra sekhara Venkata Raman, (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 light that is deflected changes in wavelength. This phenomenon is now called Raman scattering and is the result of the Raman effect.
Early years:
Venkat Raman born in Thiruvanaikaval near Tiruchirappalli Madras
Province, in British India to R. Chandrasekhara
Iyer and Parvati Ammal (Saptarshi Parvati). He was the second of their five
children. At an early age, Raman moved to the city of Vizag Andhra Pradesh. Studied
in St.Aloysius Anglo-Indian High School. His father was a
lecturer in Mathematics and physics at Presidency College (Madras) which Raman
entered in 1902 at the age of 11. 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.
Career:
In 1917, Raman
resigned from his government service and took up the newly created Palit
Professorship in Physics at the University of Calcutta. At the same time, he continued doing research at the Indian
Association for the Cultivation of Science, 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 February 28, 1928, Raman led experiments at the Indian
Association for Cultivation of Science with collaborators,
including K. S. Krishan, on the scattering of
light, when he discovered the Raman effect. A detailed
account of this period is reported in the biography by. It was instantly clear
that this discovery was of huge value. It gave further proof of the quantum
nature of light. Raman had a complicated professional relationship
with K. S. Krishan, who did not surprisingly share the
award, but is mentioned prominently even in the Nobel lecture.
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, and was disappointed when the Nobel
Prize went to Richardson in 1928 and to de
Broglie in 1929. He was so confident of winning the prize in 1930
that he booked tickets in July, even though the awards were to be announced in
November, and would scan each day's newspaper for announcement of the prize,
tossing it away if it did not carry the news. He did eventually win the
1930 Nobel Prize in Physics "for his work on the scattering
of light and for the discovery of the effect named after him". 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 the tabla and the mridangam.
Raman and his
student, Nagendra Nath, of Mim high school, 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.
In 1934, Raman became the assistant director of the Indian
Institute of Science in Bangalore, where two
years later he continued as a professor of physics. 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 CV Chemical and Manufacturing Co. Ltd. in 1943 along with Dr.Krish namurthy. The Company during its 60 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 behavior 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 behavior 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.C.V. 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 elected a Fellow of the
Royal Society early in his career (1924) and knighted in
1929. In 1930 he won the Nobel Prize in Physics. In
1941 he was awarded the Franklin Medal. In 1954 he was
awarded the Bharat Ratna. He was also awarded the Lenin Peace Prize in
1957. In 1998, the American Chemical Society and Indian
Association for the Cultivation of Science recognized 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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