Low-temperature specific heat of rare-earth-doped silicate glasses

Article

关键词: DEPENDENT SPECIFIC-HEAT;    STRUCTURAL MODEL GLASS;    THERMAL-CONDUCTIVITY;    VITREOUS SILICA;    PRESSURE;    RELAXATION;    SYSTEMS;    POLYMER;   

DOI  :  10.1103/PhysRevB.53.2179

来源: SCIE

【 摘 要 】

The specific heat C-upsilon of Pr3+- and Eu3+-doped silicate glasses has been determined between 0.1 and 10 K. Below about 5 K, C-upsilon proportional to T-1+upsilon with upsilon=0.0-0.3. This dependence is characteristic for the two-level-system (TLS) contribution to the specific heat, C-upsilon(TLS). The values of C-upsilon(TLS) and upsilon noticeably vary with the chemical nature and the concentration of the glass modifiers. The number of TLS in samples of almost identical composition is significantly larger for the Pr3+ doped than for the Eu3+ doped and the undoped glass. Above 5 K, the T-3-phonon term and the T-5 term associated with soft localized vibrations also contribute to C-upsilon. The results do not point to a correlation between the T-1+upsilon and the higher-order terms.

【 授权许可】

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