Light-driven permanent transition from insulator to conductor
Light-driven permanent transition from insulator to conductor
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DOI：
10.1103/physrevb.104.245208
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发表时间：
2020-03
影响因子：
3.7
通讯作者：
Farida Selim;D. Rana;S. Agarwal;Minhazul Islam;A. Banerjee;B. Uberuaga;P. Saadatkia;P. Dulal;N. Adhikari;M. Butterling;M. Liedke;Andreas Wagner
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文献类型：
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作者：
Farida Selim;D. Rana;S. Agarwal;Minhazul Islam;A. Banerjee;B. Uberuaga;P. Saadatkia;P. Dulal;N. Adhikari;M. Butterling;M. Liedke;Andreas Wagner
从绝缘体到导体的转变可以在某些材料中实现，但需要改变原子的排列及其电子构型。这通常是通过掺杂来实现的。在这里，我们揭示了一种机制的晶格可能采取诱导这样的过渡。我们表明，有限的曝光子带隙光引起的绝缘氧化物Ga 2 O3的9个数量级的电子传导增加的永久性转变从绝缘体状态到导体状态。光激发修改的电荷状态的O-空位和本地化的电子的重新分配，导致大量的结构畸变的晶格中，被证明是潜在的机制。它改变了态密度，并引入了新的稳定态，具有较浅的能级，导致了这种有趣的行为。我们认为，这种机制可能会发生在其他宽带隙金属氧化物，导致其电子性质的急剧修改。
The transition from insulator to conductor can be achieved in some materials but requires modification of both the arrangement of atoms and their electronic configurations. This is often achieved by doping. Here we reveal a mechanism the lattice may adopt to induce such a transition. We show that limited exposure to sub-bandgap light caused a permanent transition from an insulator state to a conductor state in the insulating oxide Ga2O3 with 9-orders of magnitude increase in electronic conduction. Photoexcitation modifies the charge state of an O-vacancy and the redistribution of the localized electrons, leading to a massive structural distortion in the lattice that is shown to be the underlying mechanism. It modifies density of states and introduces new stable states with shallower energy levels, leading to this intriguing behavior. We suggest that this mechanism may occur in other wide bandgap metal oxides leading to drastic modification in their electronic properties.