Sergio Pereira da Silva Porto, Brazilian physicist (Niterói, Rio de Janeiro State 19 January 1926 – Novosibirski, Siberia 21 June 1979) 

Recognized as world authority in spectroscopy and laser

His laboratory at Bell Labs became one of the most important laboratories in the field of solid state spectroscopy 

Authored over 150 papers

First to use laser radiation as an excitation source in Raman spectroscopy 

Employed maser radiation to minimize response time and increase efficiency in generating physical effects

With D. L. Wood. Ruby optical maser as a Raman source. Optical Society of America 52(3): 1962

With H. Kogelnik first to obtain Raman spectra using He-Ne continuous laser (1963)

With N. Jannuzzi. New singlet transitions in the near infrared spectrum of molecular hydrogen. Journal of Molecular Spectroscopy, 11(15):378-384, 1963.

With A.A. Ballman & A. Yariv. Calcium Niobate Ca(NbO3)2: a new laser host crystal. J. Appl. Physics. American Institute of Physics, 34(11): 3155 – 3136, 1963.

First to observe Raman scattering from F centers

With J.M. Worlock. Raman scattering by F centers. Phys. Rev. Lett. 15:697-9, 1965

Co-discovered thermal lens effect

With J.P. Gordon, R.S. Moore, J.R. Whinnery & R.C. C. Leite. Long transient effects in laser with insert liquid samples. J. Appl. Physics 36:3, 1965

First to observe polaritons in ionic crystals

With B. Tell & T.C. Damen. Near forward Raman scattering in zinc oxide. Phys. Rev. Lett. 16:450-2, 1966

Introduced Porto notation

With T.C. Damen & B. Tell. Raman effect in zinc oxide. Phys. Rev. 142:570-4, 1966

First to observe light scattering  from spin waves

With P. A. Fleury, L.E. Cheesman & H.J. Guggenheim. Light scattering by spin waves in FeF₂. Phys. Rev. Lett. 17:84-7, 1966

Co-discovered resonance Raman effect

With R. C. C. Leite. Enhancement of the Raman cross section in Cdc  due to resonant Absorption. Physical Review Letters 17:538, 1966 

First to observe optical activity in Raman spectra

With J.F. Scott. Longitudinal and transverse optical lattice vibrations in quartz. Phys. Rev. 161:903-10, 1967

Observed Raman cross-section of gases

With A. Weber, L.E. Cheesman & J.J. Barrett. High resolution Raman spectroscopy of gases with CW-laser excitation. J. Optic Soc. Am. 5:9-28, 1967

Observed anti-symmetric electronic Raman scattering

With A. Kiel, T.C. Damen, S. Singh & F. Varsanyi. Asymmetry in the electronic and phonon Raman effects in CeCl₃. IEEE J. Quant. Elect. 4:318, 1968

With A. Kiel. Selection rules for electronic Raman effect. J. Molecular Spectroscopy 32(3):458-68, 1969 

Observed symmetry-forbidden first-order Raman spectra in disordered solids

With P.F. Williams. Symmetry-forbidden resonant Raman scattering in Cu2O. Phys. Rev. B 8:1782-5, 1973 

Generalized Lyddane-Sachs-Teller relation for ordered-disordered crystals 

With A.S. Chaves. Generalized Lyddane-Sachs-Teller relation. Solid State Communications 13:865-8, 1973

Observed dynamic disorder in crystals using Raman scattering

With A. S. Chaves & R.S. Katiyar. Coupled modes with A1 symmetry in tetragonal BaTiO₃. Phys. Rev. B 10:3522-33, 1974

Discovered a process for obtaining heavy water (1979)

Presented theoretical methods for determining basis groups applicable to the determination of selection rules in crystals

With D.L. Rousseau. Normal mode distribution. J. Raman Spectr. 10:253, 1981

CONTRIBUTIONS TO MEDICINE AND OTHERS

With João Alberto de Holanda Freitas, Dimitrios G. Bozinis, & Antonio F.S. Penna performed the world’s first use of argon laser in glaucoma surgery (1975)

Developed the first in the world technique of tympanum transplant in man employing laser

With L. H. Escudero, A.O. Castro, M. Drumond, D.G. Bozinis, A.F.S. Penna & E. Gallego-Lluesma. Argon laser in Human Tympanoplasty. American Medical Association 105:252, 1979

Proposed using laser radiation for isotopic separation of uranium (1970s)

With Claudio Rodrigues, José Alberto Amarante, Spero Penha Morato & Othon Luiz Pinheiro da Silva used laser radiation for isotopic separation of uranium

Proposed using laser for uranium isotopic separation

DEVICES/PATENTS

A quantitative and Easily operated x – rays detecter. May 1961

With C. A. Arguello & D.L. Rousseau. A Double beam raman spectrometer.

With D. Landon. A tandem spectrometer to detect laser – exited Raman radiation. Appl. Optics. 4: 762, 1962.

With R. C. C. Leite. A simple method for calibration of ruby laser output. Sep. Proc. IEEE 51(4): 606, 1963.

With C. T.Lin, T. D. Z. Atvars et al. A low cost and high efficiency helium recycling system for CO2 laser.

With A. Szule, J. Pereira Neto, J. Rezende et al. Construction and perfomance of a high resolution grating spectrometer. Anais Academia Brasileira de Ciências, 1960. 32(1): 25-30, 1960.

With Gary D. Boyd, Phase – Matched Raman Radiation Amplifier and Oscillator. U.S. Patent Office jan. 24, 1967.

With N. Nassau & A. Yariv. Optical maser comprising the active medium CaWO4:Pr. U. S. Patent Office no 3,258,716, 258, 716. jun. 28, 1966.

With W. Proffitt, L.M. Fraas & P. Cervenka. An interferometric rejection filter for Raman spectroscopy. Appl. Opt. 10:531, 1971