Al20Te75X5 (X = Si, Ge, As, Sb) glasses prepared by the melt quenching method exhibit threshold switching. Local structure of these glasses studied by 27Al MAS-NMR measurements reveals that Al is in four-, five- and sixfold coordination. For Al to be in higher coordination states, Te transfers its lone pair electrons. Due to the higher coordinated Al and Te, the cross-linking in the network increases. The increased cross-linking and rigidity constraint the structural reorganization required for memory switching, resulting in the observed threshold switching. Interestingly, glass transition and crystallization temperatures were found to be high for Al20Te75Si5 glass and low for Al20Te75Sb5 glass. Also, the bond energy of Si–Te is higher than the bond energy of Sb–Te. Correspondingly, the threshold voltage is high for Al20Te75Si5 glass and low for Al20Te75Sb5 glass. The [6]Al site peak shows a split which may offer greater insight into the structure of these glasses.

中文翻译：

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Al20Te75X5（X = Si、Ge、As、Sb）玻璃的局部结构和电开关

通过熔体淬火方法制备的 Al20Te75X5 (X = Si、Ge、As、Sb) 玻璃表现出阈值转换。通过 27Al MAS-NMR 测量研究的这些玻璃的局部结构表明，Al 处于四、五和六重配位。为了使 Al 处于更高的配位状态，Te 会转移其孤对电子。由于较高的 Al 和 Te 配位，网络中的交联增加。增加的交联和刚性限制了内存切换所需的结构重组，导致观察到的阈值切换。有趣的是，发现 Al20Te75Si5 玻璃的玻璃化转变温度和结晶温度较高，而 Al20Te75Sb5 玻璃的玻璃化转变温度和结晶温度较低。此外，Si-Te 的键能高于 Sb-Te 的键能。相应地，Al20Te75Si5 玻璃的阈值电压高，Al20Te75Sb5 玻璃的阈值电压低。[6]Al 位点峰显示分裂，可以更深入地了解这些玻璃的结构。