title: A fast dynamic mode in rare earth based glasses.
abstract: Metallic glasses (MGs) usually exhibit only slow β-relaxation peak, and the signature of the fast dynamic is challenging to be observed experimentally in MGs. We report a general and unusual fast dynamic mode in a series of rare earth based MGs manifested as a distinct fast β'-relaxation peak in addition to slow β-relaxation and α-relaxation peaks. We show that the activation energy of the fast β'-relaxation is about 12RTg and is equivalent to the activation of localized flow event. The coupling of these dynamic processes as well as their relationship with glass transition and structural heterogeneity is discussed.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: L Z
authors.initials: LZ
authors.lastname: Zhao
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: R J
authors.initials: RJ
authors.lastname: Xue
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Z G
authors.initials: ZG
authors.lastname: Zhu
authors.affiliation: Dipartimento di Fisica, Università di Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy.
authors.forename: K L
authors.initials: KL
authors.lastname: Ngai
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: W H
authors.initials: WH
authors.lastname: Wang
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: H Y
authors.initials: HY
authors.lastname: Bai