论文标题
激光兴奋的金属中的能量放松和电子音波耦合
Energy relaxation and electron-phonon coupling in laser-excited metals
论文作者
论文摘要
电子温度的第一个原理框架对电子温度的第一个原理框架进行了研究，最高$ t_e = 50000 $ k，同时考虑了基态的晶格，研究了。研究了两种典型但不同复杂的金属，即铝和铜。为了合理地考虑电子激发效应，我们采用有限的温度密度功能理论和线性响应来确定状态的电子 - 温度依赖性Eliashberg功能和电子密度。在这三个依赖分支的电子 - 音波耦合强度中，纵向声学模式在此处考虑的所有温度中在电子音波耦合中起主要作用K与其他结果表现出良好的一致性。为了提高电子温度，我们显示了Eliashberg功能的$ t = 0 $近似的限制。我们目前的工作提供了有关声子动力学的丰富观点，这将有助于提高对超快速激光 - 金属相互作用能量流的潜在机制的见解。
The rate of energy transfer between electrons and phonons is investigated by a first principles framework for electron temperatures up to $T_e=50000$ K while considering the lattice at ground state. Two typical but differently complex metals are investigated, namely Aluminium and Copper. In order to reasonably take the electronic excitation effect into account, we adopt finite temperature density functional theory and linear response to determine the electron-temperature-dependent Eliashberg function and electron density of states. Of the three branch-dependent electron-phonon coupling strengths, the longitudinal acoustic mode plays a dominant role in the electron-phonon coupling for Aluminium for all temperatures considered here, but for Copper it only dominates above an electron temperature of $T_e=40000$ K. The second moment of the Eliashberg function and the electron phonon coupling constant at room temperature $T_e=315$ K show good agreement with other results. For increasing electron temperatures, we show the limits of the $T=0$ approximation for the Eliashberg function. Our present work provides a rich perspective on the phonon dynamics and this will help to improve insight into the underlying mechanism of energy flow in ultra-fast laser-metal interaction.
