QuickNote | Introduction
| Mathematical Analysis | Applet Tutorial | Applet
Worksheet | Quiz | SPICE/CAD
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- On the left hand side, the Fermi function f(E) is plotted. On the right
hand side, discrete states (localized states) are shown. For E > EF,
f(E) approaches zero. This means that the energy states are vacant (no
electron occupies the state). For E < EF, f(E) approaches
unity. This means that an energy state is occupied by an electron with
- Use mouse to drag EF up or
down. Observe the electron occupying or vacating the states. The probability
function f(E) is only relative to EF. EF is called
the Fermi level and is the central parameter in deciding the number of
electrons at a given energy E.
- Change the Temperature using the scroll bar at the bottom of the applet.
Observe its effect on f(E) and on the electron distribution. At a higher
T, the electron distribution is more gradual: the electron number changes
more slowly with E. This is because the higher thermal energy kT promotes
more electrons from lower states to higher states.