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This article is cited in 11 scientific papers (total in 11 papers)
CONDENSED MATTER
Phonons in YB$_6$ and LaB$_6$: Effects of temperature and pressure
Yu. S. Ponosova, N. Yu. Shitsevalovab a Mikheev Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, Yekaterinburg, 620090, Russia
b Frantsevich Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, vul. Krzhizhanovs’koho 3, Kyiv, 03680, Ukraine
Abstract:
Raman scattering by phonons in YB$_6$ and LaB$_6$ has been studied in wide temperature ($8$–$800$ K) and pressure (up to $10$ GPa) ranges. Acoustic phonons in both hexaborides exhibit anomalous softening with a decrease in the temperature. The positive isothermal Grüneisen coefficient of these modes in YB$_6$ appears to be an order of magnitude lower than the absolute value of the negative isobaric coefficient, which indicates the dominating role of temperature effects. The temperature shifts of the vibration frequencies of the B sublattice in YB$_6$ caused by phonon interactions have the opposite sign and exceed the respective shifts in LaB$_6$.
Received: 15.07.2015
Citation:
Yu. S. Ponosov, N. Yu. Shitsevalova, “Phonons in YB$_6$ and LaB$_6$: Effects of temperature and pressure”, Pis'ma v Zh. Èksper. Teoret. Fiz., 102:5 (2015), 327–332; JETP Letters, 102:5 (2015), 295–300
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https://www.mathnet.ru/eng/jetpl4721 https://www.mathnet.ru/eng/jetpl/v102/i5/p327
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Abstract page: | 140 | Full-text PDF : | 35 | References: | 35 | First page: | 8 |
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