The glasses of composition (100 − x)TeO2–xCuO (x = 10, 20, 30, 40, 50 mol%) were prepared by melt quenching method. Differential Scanning Calorimetry (DSC), DC conductivity, Electron Spin Resonance (ESR), and magnetization measurements were undertaken on the glass samples. The glass-transition temperature, T g, decreases and the thermal stability (ΔT = T o − T g) increases with the increase in CuO content. The electrical conduction in these glasses is due to polaron hopping mechanism in the adiabatic regime. The ESR spectra of the x = 10 glass consists of a broad symmetrical line characteristic of Cu2+ clusters. The ESR signal linewidth increases and intensity decreases drastically with increase in CuO content from 10 to 20 mol%. No ESR signal could be observed for the glass samples with x ≥ 40. The absence of EPR signal is ascribed to antiferromagnetic interactions between the Cu2+ clusters. The magnetization measurements indicate all the samples to be in paramagnetic state. The M–H plots show a small hysteresis loop in the low-field region. These studies indicate the coexistence of antiferromagnetic (AFM) as well as ferromagnetic (FM) interactions between Cu 2+ ions in these glasses. The significant change in the properties of the glass at x = 20 is ascribed to the structural changes caused by CuO in the glass matrix.
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机译：通过熔融淬火法制备组成为（100-x）TeO 2 -xCuO（x = 10、20、30、40、50 mol％）的玻璃。对玻璃样品进行了差示扫描量热法（DSC），直流电导率，电子自旋共振（ESR）和磁化强度测量。随着CuO的增加，玻璃化转变温度T g 降低，热稳定性（ΔT= T o -T g ）增加内容。这些玻璃中的导电是由于绝热状态下的极化子跳跃机制引起的。 x = 10玻璃的ESR光谱由Cu 2 + 团簇的宽对称线特征组成。随着CuO含量从10 mol％增加到20 mol％，ESR信号线宽增加且强度急剧降低。对于x≥40的玻璃样品，没有观察到ESR信号。没有EPR信号归因于Cu 2 + 团簇之间的反铁磁相互作用。磁化测量表明所有样品均处于顺磁性状态。 MH曲线在低场区域显示出一个小的磁滞回线。这些研究表明在这些玻璃中，Cu 2 + 离子之间反铁磁（AFM）以及铁磁（FM）相互作用共存。在x = 20时，玻璃性能的显着变化归因于玻璃基质中CuO引起的结构变化。
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