论文标题
两波段超导体MGB $ _2 $的高级非线性Terahertz探测：第三阶和第五阶谐波生成
High-order nonlinear terahertz probing of the two-band superconductor MgB$_2$: Third- and fifth-order harmonic generation
论文作者
论文摘要
我们报告了由强烈的Terahertz电磁脉冲驱动的两波段超导体MGB $ _2 $中的高阶谐波生成。三阶和五阶谐波在时域解决，并根据温度和越过超导相边界的应用磁场进行研究。超导阶段中的高阶谐波反映了MGB $ _2 $中超导顺序参数的非平衡动力学，这是通过非线性耦合到Terahertz字段进行探测的。观察到的非线性响应的温度和场依赖性允许建立超导相图。
We report on high-order harmonic generation in the two-band superconductor MgB$_2$ driven by intense terahertz electromagnetic pulses. Third- and fifth-order harmonics are resolved in time domain and investigated as a function of temperature and in applied magnetic fields crossing the superconducting phase boundary. The high-order harmonics in the superconducting phase reflects nonequilibrium dynamics of the superconducting order parameter in MgB$_2$, which is probed via nonlinear coupling to the terahertz field. The observed temperature and field dependence of the nonlinear response allows to establish the superconducting phase diagram.
