论文标题
热电子非线性耦合的两光束耦合
Two-beam coupling by a hot electron nonlinearity
论文作者
论文摘要
透明的导电氧化物（例如依赖二锡氧化物（ITO））具有在零（ENZ）波长附近的Epsilon的记录的光学非线性，具有有效的全光功能的潜力。全光应用通常涉及多个梁，但是梁之间的相干相互作用以前尚未在具有热电子非线性的材料中讨论。在这里，我们研究了ITO中ENZ处的光学非线性，并表明空间和时间干扰在两个光束几何形状中具有重要的后果。我们的泵探针结果揭示了偏振依赖性的瞬态，该瞬时通过将泵光的瞬间衍射到探针方向上解释，该瞬时通过泵探针干扰产生的温度光栅。我们进一步表明，这种效果允许通过调谐频率或chirp来调整非线性。对强和超快的非线性具有很好的控制，可以在全光神经网络，纳米光学和光谱法中进行应用。
Transparent conductive oxides such as indium tin oxide (ITO) bear the potential to deliver efficient all-optical functionality due to their record-breaking optical nonlinearity at epsilon near zero (ENZ) wavelengths. All-optical applications generally involve more than one beam, but the coherent interaction between beams has not previously been discussed in materials with a hot electron nonlinearity. Here we study the optical nonlinearity at ENZ in ITO and show that spatial and temporal interference has important consequences in a two beam geometry. Our pump-probe results reveal a polarization-dependent transient that is explained by momentary diffraction of pump light into the probe direction by a temperature grating produced by pump-probe interference. We further show that this effect allows tailoring the nonlinearity by tuning frequency or chirp. Having fine control over the strong and ultrafast ENZ nonlinearity may enable applications in all-optical neural networks, nanophotonics, and spectroscopy.
