论文标题
电子能量隙闭合和金属 - 绝缘体过渡中的液体氢
Electronic energy gap closure and metal-insulator transition in dense liquid hydrogen
论文作者
论文摘要
使用量子蒙特卡洛（QMC）计算，我们研究了在高压下在液体氢中观察到的绝缘剂 - 金属过渡。在从分子到原子液体的过渡的临界温度以下，基本电子间隙闭合突然发生，较小的不连续性反映了状态热力学方程中弱的一阶转变。在临界温度之上，分子解离设置在差距仍开放的同时。当差距闭合时，非对角线还原密度矩阵的衰减表明，液体进入了一个无间隙但局部的相：绝缘液和金属液体之间存在跨界。与不同的DFT函数相比，我们的QMC计算为靠近带边的状态的基本差距和电子密度提供了更大的值，这表明来自DFT的光学性质可能受益于误差取消。
Using Quantum Monte Carlo (QMC) calculations, we investigate the insulator-metal transition observed in liquid hydrogen at high pressure. Below the critical temperature of the transition from the molecular to the atomic liquid, the fundamental electronic gap closure occurs abruptly, with a small discontinuity reflecting the weak first-order transition in the thermodynamic equation of state. Above the critical temperature, molecular dissociation sets in while the gap is still open. When the gap closes, the decay of the off-diagonal reduced density matrix shows that the liquid enters a gapless, but localized phase: there is a cross-over between the insulating and the metallic liquids. Compared to different DFT functionals, our QMC calculations provide larger values for the fundamental gap and the electronic density of states close to the band edges, indicating that optical properties from DFT potentially benefit from error cancellations.
