Raman phonon anomalies in Sr(Fe1-xCox)2As2

• 作者: Yanxing Yang Hewei Zhang Haizheng Zhuang
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC,AND OPTICAL PROPERTIES
• 页码范围: 635-639
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/1674-1056/ac0cd6

摘要

Phonon anomalies have been reported in iron-pnictide superconductors indicating a diverse interplay between different orders in the materials.Here,we report Raman scattering measurements on Sr(Fel-xCox)2As2 (x =0 and x =0.04)single crystals in the B2g symmetry with respect to a 1 Fe unit cell.Upon cooling,we observe a larger split (13 cm-1)of Eg Raman phonon modes pertaining to in-plane Fe and As displacements as the crystals undergo the tetragonal-to-orthorhombic structural phase transition,although a considerable split (9 cm-1) has been reported in Ba(Fel-xCox)2As2.Furthermore,the splitting of Eg phonon modes is strongly reduced upon doping.We perform an order-parameter analysis revealing a similar doping dependence of Eg phonon splitting as reported in other compounds of the 122 family,indicating these phonon anomalies widely exist in 122 iron-based superconductors and might share the same mechanisms.