欧姆定律.pdf

1 1 j E Ej σ σ σE EEj σ σρ σ ρ 1 2 SI -1Ω−1m-1 ΩmΩ 2 0 12 ε σ −⋅EEn j S, σ l ⋅⋅∆ S dl Il djl dE ρ ρϕ S dl R ρ R U IIRU 3 R 2-1 2-1 /Ω⋅m /Ω⋅m 1.67 10-8 0.64 9.71 10-8 1.4 10-5 9.71 10-8 10101014 1.59 10-8 1 1013 5.51 10-8 4.4 10-2 9.58 10-8 2 1019 100 10-8 1081011 3 1 0 tαρρ ρ tρ0 0α 04 4 1 0 tRRα 000000586. 0003985. 01 2 0 ttRR− R tR0 0 4 Gleiter CuPdFe Ag 18nm 11nm α, α 5 2-37 Ag a 20nm 12nm B 18nm 11nm c 11nm 11nm 6 α 5 RURIUIP/ 22 tRIA∆∆ 2 tRIAQ∆∆ 2 R p σ 2 j Ejp⋅ 7 1 t0 v0 2 0 2 0 Et m q 2 1 tvat 2 1 tvs t v0 t 2 tE m q 2 1 s t v0 v0t τ s u t N t tdt e-t/τdt 8 22 2τt E m q NNqujτ 2 σ τσ m q N 2 τ v λ τλv σλTv ∝σ T 1 ∝σ 2 -- 9 T0KN N/2 εF7.03eV, TF8l 000 K ε3εF/5 T0K T0 kT εF T300K kT0026eV kT , v vF m v F F ε2 , 100 vF v 16 10 ττ σ, j E I U 1 E T τ τT τ 10-1310-14s T10-14s υ1014Hz, 1011Hz E103104V m-1 u v , E j E 2 λλ 11 3 I U 2-38 2-38 4 σ 5 j E σ V I 0 12 1826 Georg Simon Ohm 17891854 ---Ohm Ohm 2-39 Georg Simon Ohm Coulom 40 Volta 20 Ohm 1825 5 Ohm 1825 7 Ohm Ohm 1826 4 Ohm 13 Volta Ohm Poggendorff Ohm F x xb a F ab F x Ohm a b a a Ohm b b F a x b xb Ohm Ohm Ohm F x a b Ohm 1826 4 Ohm Ohm l a kSF 14 F l S k Ohm a Ohm Ohm 1827 Ohm Ohm Ohm Ohm Ohm Ohm LenzWeberGauss 19 30 40 Ohm 1841 Copley Ohm Ohm σ εOhm jσE Dεrε0E, Br0H Maxwell Ohm *200155-60