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2.5: The Density of States

  • Page ID
    50020
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    To determine whether a material is a metal or an insulator, and to calculate the magnitude of the current under applied bias, we need the density of states (DOS), which as you recall is a measure of the number of states in a conductor per unit energy. In this part, we will calculate the DOS for a variety of different conductors.

    Screenshot 2021-04-15 at 21.25.06.png
    Figure \(\PageIndex{1}\): Partly filled states give metallic behavior, while completely filled or empty states correspond to insulators or semiconductors.

    To calculate the density of states we will employ two assumptions: (i) we will model the conductor as a homogeneous box, and (ii) we will assume periodic boundary conditions.


    This page titled 2.5: The Density of States is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Marc Baldo (MIT OpenCourseWare) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.