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  2. Charge carrier density - Wikipedia

    en.wikipedia.org/wiki/Charge_carrier_density

    In this case, the carrier density (in this context, also called the free electron density) can be estimated by: [5] ... Carrier density (1/cm 3) at 300K Copper: 1

  3. Drift velocity - Wikipedia

    en.wikipedia.org/wiki/Drift_velocity

    Copper has one free electron per atom, so n is equal to 8.5 × 10 28 electrons per cubic metre. Assume a current I = 1 ampere, and a wire of 2 mm diameter (radius = 0.001 m). This wire has a cross sectional area A of π × (0.001 m) 2 = 3.14 × 10 −6 m 2 = 3.14 mm 2. The elementary charge of an electron is e = −1.6 × 10 −19 C.

  4. Free electron model - Wikipedia

    en.wikipedia.org/wiki/Free_electron_model

    In solid-state physics, the free electron model is a quantum mechanical model for the behaviour of charge carriers in a metallic solid. It was developed in 1927, [1] principally by Arnold Sommerfeld, who combined the classical Drude model with quantum mechanical Fermi–Dirac statistics and hence it is also known as the Drude–Sommerfeld model.

  5. Electron mobility - Wikipedia

    en.wikipedia.org/wiki/Electron_mobility

    Then the electron mobility μ is defined as =. Electron mobility is almost always specified in units of cm 2 /(V⋅s). This is different from the SI unit of mobility, m 2 /(V⋅s). They are related by 1 m 2 /(V⋅s) = 10 4 cm 2 /(V⋅s). Conductivity is proportional to the product of mobility and carrier concentration. For example, the same ...

  6. Electron density - Wikipedia

    en.wikipedia.org/wiki/Electron_density

    Spin density is electron density applied to free radicals. It is defined as the total electron density of electrons of one spin minus the total electron density of the electrons of the other spin. One of the ways to measure it experimentally is by electron spin resonance, [14] neutron diffraction allows direct mapping of the spin density in 3D ...

  7. Copper - Wikipedia

    en.wikipedia.org/wiki/Copper

    The maximum possible current density of copper in open air is approximately 3.1 × 10 6 A/m 2, above which it begins to heat excessively. [17] Copper is one of a few metallic elements with a natural color other than gray or silver. [18] Pure copper is orange-red and acquires a reddish tarnish when exposed to air.

  8. Fermi surface - Wikipedia

    en.wikipedia.org/wiki/Fermi_surface

    Fig. 1: Fermi surface and electron mo­mentum density of copper in the reduced zone schema measured with 2D ACAR. [6]Consider a spin-less ideal Fermi gas of particles. . According to Fermi–Dirac statistics, the mean occupation number of a state with energy is give

  9. Effective mass (solid-state physics) - Wikipedia

    en.wikipedia.org/wiki/Effective_mass_(solid...

    The optical Hall effect is an emerging technique for measuring the free charge carrier density, effective mass and mobility parameters in semiconductors. The optical Hall effect measures the analogue of the quasi-static electric-field-induced electrical Hall effect at optical frequencies in conductive and complex layered materials.