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In quantum electrodynamics (QED), the Schwinger limit is a scale above which the electromagnetic field is expected to become nonlinear. The limit was first derived in one of QED's earliest theoretical successes by Fritz Sauter in 1931 and discussed further by Werner Heisenberg and his student Hans Heinrich Euler. The limit, however, is commonly named in the literature for Julian Schwinger, who derived the leading nonlinear corrections to the fields and calculated the rate of electron–positron pair production in a strong electric field. The limit is typically reported as a maximum electric field or magnetic field before nonlinearity for the vacuum of
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Non linear piezoelectric effects in polar semiconductors are the manifestation that the strain induced piezoelectric polarization depends not just on the product of the first order piezoelectric coefficients times the strain tensor components but also on the product of the second order piezoelectric coefficients times products of the strain tensor components. The idea was put forward for zincblende GaAs and InAs semiconductors since 2006, and then extended to all commonly used wurtzite and zincblende semiconductors. Given the difficulty of finding direct experimental evidence for the existence of these effects, there are different schools of thought on how one can calculate reliably all the piezoelectric coefficients. On the other hand, there is widespread agreement on the fact that non linear effects are rather large and comparable to the linear terms. Indirect experimental evidence of the existence of these effects has been reported in the literature in relation to GaN and InN semiconductor optoelectronic devices.
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Maria Cristina Marchetti is an Italian-born, American theoretical physicist specializing in statistical physics and condensed matter physics. In 2019, she received the Leo P. Kadanoff Prize of the American Physical Society. She held the William R. Kenan, Jr. Distinguished Professorship of Physics at Syracuse University, where she was the director of the Soft and Living Matter program, and chaired the department 2007–2010. She is currently Professor of Physics at the University of California, Santa Barbara.
Eleftherios Ν. Economou is a Greek theoretical physicist and professor emeritus at the department of physics of the University of Crete. He has contributed to various areas of theoretical condensed matter physics, starting with the study of surface plasmons during his thesis in 1969.
Electroreflectance is the change of reflectivity of a solid due to the influence of an electric field close to, or at the interface of the solid with a liquid. The change in reflectivity is most noticeable at very specific ranges of photon energy, corresponding to the band gaps at critical points of the Brillouin zone.
Louis Malter was an American physicist specializing in vacuum tube research and high-vacuum systems. He is known for his 1936 discovery of the eponymous Malter effect.
References
- ↑ Parmenter, R. H. (1953). "The Acousto-Electric Effect". Physical Review. 89 (5): 990–998. Bibcode:1953PhRv...89..990P. doi:10.1103/PhysRev.89.990. ISSN 0031-899X.
- ↑ Weinreich, Gabriel; White, Harry G. (1957). "Observation of the Acoustoelectric Effect". Physical Review. 106 (5): 1104–1106. Bibcode:1957PhRv..106.1104W. doi:10.1103/PhysRev.106.1104. ISSN 0031-899X.
- ↑ Kalameitsev, Alexander; Kovalev, Vadim; Savenko, Ivan (26 June 2019). "Valley Acoustoelectric Effect". Physical Review Letters. 122 (25): 256801. arXiv: 1906.11151 . Bibcode:2019PhRvL.122y6801K. doi:10.1103/PhysRevLett.122.256801. PMID 31347890. S2CID 195658238 . Retrieved 7 August 2019.