论文标题
由浆果曲率和量子度量介导的异常希格斯振荡
Anomalous Higgs oscillations mediated by Berry curvature and quantum metric
论文作者
论文摘要
希格斯光谱学是超导体的希格斯玻色子的研究，是研究超导性的新兴领域。在这里，我们表明浆果曲率和频带的量子度量在HIGGS模式生成中起着核心作用。即使在频段曲率消失的常规贡献时，它们也可以检测到希格斯玻色子。此外，我们表明，当通过浆果连接介导时，希格斯模式可以将HIGGS模式线性地与外部电磁场搭配。结果，除了众所周知的第三次谐波生成外，我们还预测了第二次谐波生成的存在。我们通过考虑由Harper-Hubbard模型实现的平坦带超导体进一步阐明了我们的理论，并表明几何希格斯模式由频带Chern数量限制。我们在扭曲的双层石墨烯中证明了几何诱导的希格斯模式的存在，当在魔法角度以近乎平坦的频段实现超导性时。
Higgs spectroscopy, the study of Higgs bosons of a superconductor, is an emerging field in studying superconductivity. Here we show that the Berry curvature and the quantum metric of bands play a central role in the Higgs mode generation. They allow the detection of Higgs bosons even when the conventional contribution from the band curvature vanishes. Furthermore, we show that the Higgs mode can couple to the external electromagnetic field linearly when mediated by the Berry connection. As a result, we predict the existence of a second harmonic generation, in addition to the well-known third harmonic generation. We elucidate our theory further by considering a flat band superconductor realized by the Harper-Hubbard model and show that the geometric Higgs mode is lower bounded by the band Chern number. We demonstrate in twisted bilayer graphene the existence of the geometrically induced Higgs modes when superconductivity is realized in the nearly flat band at the magic angle.
