For a particular material, the Hall coefficient is found to be zero. The material is

Hall coefficient is defined as:

\({R_H} = \frac{{P\mu _p^2 - n\mu _n^2}}{{q{{\left( {p{\mu _p} + n{\mu _n}} \right)}^2}}}\)

\({R_H} = \frac{1}{{{\rho _c}}} = \frac{{ - 1}}{{nq}}\)

\(n = \frac{1}{{{R_H}q}}\)

We can find the electron concentration as:

\({R_H} = \frac{1}{{{\rho _c}}} = \frac{1}{{pq}}\)

\(P = \frac{1}{{{R_H}q}}\)

ρc = charge density

σ_n = nμ_nq and σ_p = pμ_pq

• Hall coefficient depends on the hole and electron concentration, and also on the mobility of carriers.
• In an insulator, the gap between the conduction band and the valence band is very high.
• Conductivity will be almost zero in the insulator
• As conductivity zero in insulator then mobility also almost zero.
• So, the hall coefficient will be zero almost for the insulator.