Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers
Discrete breather (DB) is a spatially localized vibrational mode of large amplitude with vibration frequency outside the phonon band of the crystal. DB frequency can leave phonon spectrum due to the anharmonicity of interatomic bonds owing to the fact that the frequency of a nonlinear oscillator is...
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Format: | Journal Article |
Language: | English |
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2019
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Online Access: | https://hdl.handle.net/10356/105636 http://hdl.handle.net/10220/50256 |
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author | Semenov, A. S. Bebikhov, Yu. V. Kistanov, Andrey A. |
author2 | School of Mechanical and Aerospace Engineering |
author_facet | School of Mechanical and Aerospace Engineering Semenov, A. S. Bebikhov, Yu. V. Kistanov, Andrey A. |
author_sort | Semenov, A. S. |
collection | NTU |
description | Discrete breather (DB) is a spatially localized vibrational mode of large amplitude with vibration frequency outside the phonon band of the crystal. DB frequency can leave phonon spectrum due to the anharmonicity of interatomic bonds owing to the fact that the frequency of a nonlinear oscillator is amplitude dependent. In the case of soft (hard) anharmonicity the nonlinear oscillator frequency decreases (increases) with amplitude. Crystals having a gap in the phonon spectrum can, in principle, support the so-called gap DBs, i.e., DBs with frequencies within the gap. The alkali halide NaI crystal possesses a wide gap in the phonon spectrum and the existence of gap DBs in this crystal has been shown by Kiselev and Sievers with the use of the molecular dynamics method. Later on, several experimental works have been undertaken to support the results of the numerical study and also the possibility of energy exchange between two closely positioned DBs was shown by atomistic simulations. In the present study the energy exchange between DBs in larger clusters is simulated by molecular dynamics. It is shown that the energy initially given to the DB cluster stays in the localized form for a long time (hundreds of DB oscillation periods) even though the energy can travel from one lattice site to another and even polarization of DBs can change. These results contribute to our better understanding of the mechanism of energy localization and transport in crystals. |
first_indexed | 2024-10-01T03:31:30Z |
format | Journal Article |
id | ntu-10356/105636 |
institution | Nanyang Technological University |
language | English |
last_indexed | 2024-10-01T03:31:30Z |
publishDate | 2019 |
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spelling | ntu-10356/1056362023-03-04T17:20:38Z Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers Semenov, A. S. Bebikhov, Yu. V. Kistanov, Andrey A. School of Mechanical and Aerospace Engineering Intrinsic Localized Mode Engineering::Mechanical engineering Discrete Breather Discrete breather (DB) is a spatially localized vibrational mode of large amplitude with vibration frequency outside the phonon band of the crystal. DB frequency can leave phonon spectrum due to the anharmonicity of interatomic bonds owing to the fact that the frequency of a nonlinear oscillator is amplitude dependent. In the case of soft (hard) anharmonicity the nonlinear oscillator frequency decreases (increases) with amplitude. Crystals having a gap in the phonon spectrum can, in principle, support the so-called gap DBs, i.e., DBs with frequencies within the gap. The alkali halide NaI crystal possesses a wide gap in the phonon spectrum and the existence of gap DBs in this crystal has been shown by Kiselev and Sievers with the use of the molecular dynamics method. Later on, several experimental works have been undertaken to support the results of the numerical study and also the possibility of energy exchange between two closely positioned DBs was shown by atomistic simulations. In the present study the energy exchange between DBs in larger clusters is simulated by molecular dynamics. It is shown that the energy initially given to the DB cluster stays in the localized form for a long time (hundreds of DB oscillation periods) even though the energy can travel from one lattice site to another and even polarization of DBs can change. These results contribute to our better understanding of the mechanism of energy localization and transport in crystals. Published version 2019-10-24T05:12:22Z 2019-12-06T21:55:02Z 2019-10-24T05:12:22Z 2019-12-06T21:55:02Z 2017 Journal Article Semenov, A. S., Bebikhov, Y. V., & Kistanov, A. A. (2017). Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers. Letters on Materials, 7(2), 77-80. doi:10.22226/2410-3535-2017-2-77-80 https://hdl.handle.net/10356/105636 http://hdl.handle.net/10220/50256 10.22226/2410-3535-2017-2-77-80 en Letters on Materials © 2017 Institute for Metals Superplasticity Problems of Russian Academy of Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License. 4 p. application/pdf |
spellingShingle | Intrinsic Localized Mode Engineering::Mechanical engineering Discrete Breather Semenov, A. S. Bebikhov, Yu. V. Kistanov, Andrey A. Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers |
title | Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers |
title_full | Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers |
title_fullStr | Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers |
title_full_unstemmed | Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers |
title_short | Simulation of energy transport in crystal with NaCl structure assisted by discrete breathers |
title_sort | simulation of energy transport in crystal with nacl structure assisted by discrete breathers |
topic | Intrinsic Localized Mode Engineering::Mechanical engineering Discrete Breather |
url | https://hdl.handle.net/10356/105636 http://hdl.handle.net/10220/50256 |
work_keys_str_mv | AT semenovas simulationofenergytransportincrystalwithnaclstructureassistedbydiscretebreathers AT bebikhovyuv simulationofenergytransportincrystalwithnaclstructureassistedbydiscretebreathers AT kistanovandreya simulationofenergytransportincrystalwithnaclstructureassistedbydiscretebreathers |