Towards first-principles understanding of the metal-insulator transition in fluid alkali metals

H. Maebashi; Y. Takada

doi:10.1088/0953-8984/21/6/064205

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arXiv · 0807.1454

Towards first-principles understanding of the metal-insulator transition in fluid alkali metals

H. Maebashi·Y. Takada

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Abstract

By treating the electron-ion interaction as perturbation in the first-principles Hamiltonian, we have calculated the density response functions of a fluid alkali metal to find an interesting charge instability due to anomalous electronic density fluctuations occurring at some finite wave vector ${\bi Q}$ in a dilute fluid phase above the liquid-gas critical point. Since $|{\bi Q}|$ is smaller than the diameter of the Fermi surface, this instability necessarily impedes the electric conduction, implying its close relevance to the metal-insulator transition in fluid alkali metals.

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H. Maebashi, Y. Takada. 2008-07-09. Towards first-principles understanding of the metal-insulator transition in fluid alkali metals. https://doi.org/10.1088/0953-8984%2F21%2F6%2F064205

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