Phonons in iron: from the bulk to an epitaxial monolayer.
Phonons in iron: from the bulk to an epitaxial monolayer.
复制标题
铁中的声子：从块体到外延单层。
DOI：
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发表时间：
2007
影响因子：
8.6
通讯作者：
J. Korecki
中科院分区：
文献类型：
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作者：
S. Stankov;R. Röhlsberger;T. Ślęzak;M. Sladecek;B. Sepiol;G. Vogl;A. Chumakov;R. Rüffer;N. Spiridis;J. Łażewski;K. Parlinski;J. Korecki
材料在低维结构中的限制对声子等激发的传播有重要影响。利用同位素特异的57Fe核共振振动光谱，我们能够确定W（110）上的Fe3O4 Fe薄膜的弹性和热力学性质。随着厚度的减小，观察到平均原子位移的显著增加，与体相比较，该平均原子位移沿着增加，并且在低能量下振动模式增强。分析表明，这些偏差是由膜的两个边界处的单原子层的原子振动引起的，而膜内的原子几乎是块状振动。
The confinement of materials in low-dimensional structures has significant impact on propagating excitations like phonons. Using the isotope-specific 57Fe nuclear resonant vibrational spectroscopy we were able to determine elastic and thermodynamic properties of ultrathin Fe films on W(110). With decreasing thickness one observes a significant increase of the mean atomic displacement that goes along with an enhancement of vibrational modes at low energies as compared to the bulk. The analysis reveals that these deviations result from atomic vibrations of the single atomic layers at the two boundaries of the film, while the atoms inside the films vibrate almost bulklike.