Question

esistance with two carrier types. Problem 6.9 shows that in the drift roximation the motion of charge carriers in electric and magnetic fields does not lead to transverse magnetoresistance. The result is different with two car- rier types. Consider a conductor with a concentration n of electrons of effective mass m, and relaxation time 7,; and a concentration p of holes of effective mass ma, and relaxation time Th Treat the limit of very strong magnetic fields, ω,T 키 (a) Show, in this limit that ơyx-(n-pec/B, (b) Show that the Hall field is given by, with o,T, which vanishes if n = p. (c) Show that the effective conductivity in the x direction is r n-P, σ oc B-2. If n p, σ saturates in strong fields; that is, it approaches a limit independent of B as B-> oo

Answer 1

Given tht magneC CIC a me 0 me

Pe mb Qn MeQe me mne rin agan ne?te Pec 3 e c an

an Let Then χ written as Condutha a½6-t.fivc 'Thc Ex f e. om

ес. Then where eBTe e. miec Q. mnC In

mm C 2 Let, en C ause