热效应对带隙石墨烯中异常诱导的机电响应的影响
Thermal effect on the anomaly-induced electromechanical response in gapped graphene
AI总结：
研究了热效应对带隙石墨烯中异常诱导机电响应的影响，发现有限温度下响应呈平滑交叉，可用于分离异常电流并提取器件有效带隙和电子温度。
AI中文摘要：
带隙石墨烯的机械变形可作为涌现规范场作用于狄拉克准粒子。当该变形场与电磁场耦合至同一电流时，宇称异常会产生混合机电陈-西蒙斯响应：声子电场驱动横向电流，声子磁场束缚电荷。此前零温结果预测，当化学势越过带边时，响应会发生突变。我们表明，有限温度会用仅由温度、带隙和化学势的比值控制的通用平滑交叉取代这一尖锐特征。在绝缘区，响应几乎保持量子化；在带边附近约为温度量级的栅极窗口内，响应被圆滑化；并以受控的索末菲修正趋近于掺杂的贝里曲率结果。我们将该结果应用于两种实验有用的驱动：行弯曲波，其产生横向二次谐波电流；以及与静态波纹混合的动态声子，其产生基频信号。同一栅极-温度线形控制两种信号。这为将异常诱导电流与普通机电背景分离，并提取石墨烯器件的有效带隙和电子温度提供了直接途径。
英文摘要：
Mechanical deformation of gapped graphene can act on Dirac quasiparticles as an emergent gauge field. When this deformation field couples to the same current as the electromagnetic field, the parity anomaly produces a mixed electromechanical Chern-Simons response: a phonon electric field drives a transverse electrical current, and a phonon magnetic field binds charge. Previous zero-temperature results predict a sharp change in the response when the chemical potential crosses the band edge. We show that finite temperature replaces this sharp feature by a universal smooth crossover controlled only by the ratios of temperature, gap, and chemical potential. The response remains almost quantized in the insulating regime, is rounded over a gate window of order temperature near the band edge, and approaches the doped Berry-curvature result with a controlled Sommerfeld correction. We apply the result to two experimentally useful drives: a traveling flexural wave, which produces a transverse second-harmonic current, and a dynamic phonon mixed with a static ripple, which produces a fundamental-frequency signal. The same gate-temperature line shape controls both signals. This gives a direct way to separate the anomaly-induced current from ordinary electromechanical backgrounds and to extract the effective gap and electronic temperature in graphene devices.
