Controlling dielectrics with the electric field of light
Controlling dielectrics with the electric field of light
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DOI：
10.1038/nature11720
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发表时间：
2013-01-03
期刊：
影响因子：
64.8
通讯作者：
Krausz, Ferenc
中科院分区：
文献类型：
--
作者：
Schultze, Martin;Bothschafter, Elisabeth M.;Krausz, Ferenc
用微波场控制半导体的电学和光学性质是现代电子学、信息处理和光通信的基础。将这种控制扩展到光学频率需要宽带材料，如SiO2，这需要强电场来改变它们的物理特性（1-5）。几个周期的激光脉冲允许无损伤地暴露在每埃数伏的电场中（6），并在其电子系统中进行重大修改（6-13）。这种强度和时间限制的场可以在光周期（14）内将电介质从绝缘状态转变为导电状态。然而，将电信号控制和处理扩展到光频率取决于逆转这些效应的可行性，这些效应的速度大约与它们可以被诱导的速度一样快。在这里，我们研究了亚飞秒固态光谱，这揭示了操纵的电子结构和电介质的电极化与光的电场可逆的可行性的潜在电子过程。我们照射的电介质（熔融石英）与波形控制的近红外几个周期的光场的几伏每埃和探针的变化极紫外线吸收率和近红外反射率的时间尺度上约一百阿秒到几飞秒。场诱导的变化遵循，在一个高度非线性的方式，打开和关闭行为的驱动场，在协议的量子力学模型的预测。这种效应的超快可逆性意味着电介质的物理特性可以通过光的电场来控制，这为petahertz带宽信号的操纵提供了可能。
The control of the electric and optical properties of semiconductors with microwave fields forms the basis of modern electronics, information processing and optical communications. The extension of such control to optical frequencies calls for wideband materials such as dielectrics, which require strong electric fields to alter their physical properties(1-5). Few-cycle laser pulses permit damage-free exposure of dielectrics to electric fields of several volts per angstrom(6) and significant modifications in their electronic system(6-13). Fields of such strength and temporal confinement can turn a dielectric from an insulating state to a conducting state within the optical period(14). However, to extend electric signal control and processing to light frequencies depends on the feasibility of reversing these effects approximately as fast as they can be induced. Here we study the underlying electron processes with sub-femtosecond solid-state spectroscopy, which reveals the feasibility of manipulating the electronic structure and electric polarizability of a dielectric reversibly with the electric field of light. We irradiate a dielectric (fused silica) with a waveform-controlled near-infrared few-cycle light field of several volts per angstrom and probe changes in extreme-ultraviolet absorptivity and near-infrared reflectivity on a timescale of approximately a hundred attoseconds to a few femtoseconds. The field-induced changes follow, in a highly nonlinear fashion, the turn-on and turn-off behaviour of the driving field, in agreement with the predictions of a quantum mechanical model. The ultrafast reversibility of the effects implies that the physical properties of a dielectric can be controlled with the electric field of light, offering the potential for petahertz-bandwidth signal manipulation.