Vegard's law

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In metallurgy, Vegard's law is an approximate empirical rule which holds that a linear relation exists, at constant temperature, between the crystal lattice parameter of an alloy and the concentrations of the constituent elements.^[1]

For example, consider the semiconductor compound InP_xAs_1-x. A relation exists between the constituent elements and their assosciated lattice parameters, a, such that:

a_InPAs = xa_InP + (1 − x)a_InAs

One can also extend this relation to determine semiconductor band gap energies. Using InP_xAs_1-x as before one can find an expression that relates the band gap energies, E_g, to the ratio of the constituents and a bowing parameter b:

[edit] References

1. ^ Harvard.edu

[edit] See also

• Metallurgy
• Physics