首页|Coupling of quasi-localized and phonon modes in glasses at low frequency

Coupling of quasi-localized and phonon modes in glasses at low frequency

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
Boson peak of glasses,a THz vibrational excess compared to Debye squared-frequency law,remains mysterious in condensed-matter physics and material science.It appears in many different kinds of glassy matters and is also argued to exist in damped crystals.A consensus is that boson peak originates from the coupling of the(quasi)-localized non-phonon modes and the plane-wave-like phonon modes,but the coupling behavior is still not fully understood.In this paper,by modulating the content of localized modes and the frequencies of phonon modes,the coupling is clearly reflected in the localization and anharmonicity of low-frequency vibrational modes.The coupling enhances with increasing cooling rate and sample size.For finite sample size,phonon modes do not fully intrude into the low frequency to form a dense spectrum and they are not sufficiently coupled to the localized modes,thus there is no Debye level and boson peak is ill-defined.This suggestion remains valid in the presence of thermal motions induced by temperature,even though the anharmonicity comes into play.Our results point to the coupling of quasi-localized and phonon modes and its relation to the boson peak.

metallic glasseslow-frequency vibrational modesplane waveboson peak

段军、蔡松林、丁淦、戴兰宏、蒋敏强

展开 >

State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China

School of Engineering Science,University of Chinese Academy of Sciences,Beijing 101408,China

National Outstanding Youth Science Fund ProjectFund from the Basic Science Center for"Multiscale Problems in Nonlinear Mechanics"国家自然科学基金一般项目

121252061198810211972345

2024

10.1088/1674-1056/ad2dce

中国物理B(英文版)
中国物理学会和中国科学院物理研究所

中国物理B(英文版)

CSTPCDEI
影响因子：0.995
ISSN：1674-1056
年,卷(期)：2024.33(5)
  • 60