Mitsa V, Feher A, Petretskyi S, Holomb R, Tkac V, Ihnatolia P, Laver A
Uzhhorod National University, Pidhirna Str., 46, Uzhhorod, 88000, Ukraine.
Pavol Jozef Šafárik University in Košice, 041 54, Košice, Slovak Republic.
Nanoscale Res Lett. 2017 Dec;12(1):345. doi: 10.1186/s11671-017-2125-6. Epub 2017 May 10.
Experimental results of the thermal conductivity (k(T)) of nanostructured g-AsS during cooling and heating processes within the temperature range from 2.5 to 100 K have been analysed. The paper has considered thermal conductivity is weakly temperature k(T) dependent from 2.5 to 100 K showing a plateau in region from 3.6 to 10.7 K during both cooling and heating regimes. This paper is the first attempt to consider the k(T) hysteresis above plateau while heating in the range of temperature from 11 to 60 K. The results obtained have not been reported yet in the scientific literature. Differential curve Δk(T) of k(T) (heating k(T) curve minus cooling k(T) curve) possesses a complex asymmetric peak in the energy range from 1 to 10 meV. Δk(T) reproduces the density of states in a g(ω)/ω representation estimated from a boson peak experimentally obtained by Raman measurement within the range of low and room temperatures. Theoretical and experimental spectroscopic studies have confirmed a glassy structure of g-AsS in cluster approximation. The origin of the low-frequency excitations resulted from a rich variety of vibrational properties. The nanocluster vibrations can be created by disorder on atomic scale.
分析了纳米结构g-AsS在2.5至100 K温度范围内冷却和加热过程中的热导率（k(T)）实验结果。该论文认为，在2.5至100 K范围内，热导率k(T)对温度的依赖性较弱，在冷却和加热过程中，3.6至10.7 K范围内呈现出一个平台。本文首次尝试考虑在11至60 K温度范围内加热时高于平台的k(T)滞后现象。所获得的结果尚未在科学文献中报道。k(T)的微分曲线Δk(T)（加热k(T)曲线减去冷却k(T)曲线）在1至10 meV的能量范围内具有一个复杂的不对称峰。Δk(T)在低温和室温范围内通过拉曼测量实验获得的玻色子峰估计的g(ω)/ω表示中再现了态密度。理论和实验光谱研究在团簇近似中证实了g-AsS的玻璃态结构。低频激发的起源源于丰富多样的振动特性。纳米团簇振动可由原子尺度上的无序产生。
