Документ взят из кэша поисковой машины. Адрес оригинального документа : http://genphys.phys.msu.su/rus/lab/elmag/Lab322_E-M_2010.pdf Дата изменения: Mon Nov 1 03:25:20 2010 Дата индексирования: Mon Oct 1 23:31:46 2012 Кодировка: Поисковые слова: m 8

. ..

( )
.., .. , .. , ..



I 1 2 3 B 1





2 3 0 B


B





2010


( ) .., .. , .. , .. ­ .: . - , 2010, 20 .
­ " " (.. ) [4], " " (.. ) [4] " " (.. ) [5].


................................................................................................. 3 ............................................................................................ 3 ................................................................................... 3 " "................................................................................................ 3 ................................................................................................... 7 ....................................................................... 10 ................................................................................................. 10 ............................................................................................. 10 ................................................................................................. 11 ............................................................................... 12 1. " " .................................................................. 13 .................................................................................................................. 13 .............................................................................................. 13 2. ............................................................................ 14 .................................................................................................................. 14 .............................................................................................. 15 ........................................................................................... 15 ............................................................................................... 17 ...................................................................................... 17 1. " 3/2" ............................ 18 2. ............................................ 18 3. ......................20


-3­


e/m . ­ e/m / . . " " [1, 2] [6]- [7] [8], - . (" "). " " , , . ( ), ( ), , . , , I U , , I R = const. - .1. ( ) = U/R,

j (.. ) . () v, , , U: j = v ~ , j ~ v ~ ~ U, ­ . , . ,


-4­ . -, , , I0 ( , 3 .1). , , . I0 , . 3 /2 ( I~U ). , 12 3 , 0 U .1 - , . 1 ­ - . , (I ~ U3/2) 2 ­ - U ( 3 ­ ) , U ( 1 2 . 1). " " [1-3], I ~ U 3 /2 , I ( 1 . 1), (I << I0). I0 . " " , , D , . ox , .. (. 2). ­ , , ­ , . ,


-5­ , ( . 3). ("") . (), 2 = - , (1 ) 0 d 2 =- , (1') 2 0 dx (x) ­ , 0 ­ . ()
j = v,





0

D

x

. 2 . .

(2 )

v(x) :
12 mv = e , 2 (3 )

e ­ , (x = 0) . , .. v(0) = 0. (x) . , , :

I = - jS = -vS = const ,

(4 )

I ­ , j = v ­ , S ­ , . v(x) , () , (3), (4) 1 1 |()| ~ ~ . v (2)-(4) v, , (x) d 2 a 2 = , (4 ) dx 2


-6­
I m . 0 S 2e E = ­d/dx (.. ). , , dx = d/E, d 2 d d d d dE = = -E =E . d dx d dx 2 dx dx

a 2 =

dE a 2 d = EdE = a 2 . E d

,
E 2 ( x ) - E 2 (0) = 4a 2 1 / 2 .
, v, , Ex v ~ x2
/3

~x x

0

0 ~ ­x­
2/3

Ex ~ ­ x1

/3

. 3 (), v(x), () () . ­ () .



~ x4

/3

D

(0) . , , , , , . , , . , (0) , (0) = 0. (5 ) d E ( x) = - = ± 2a1 / 4 dx -1 / 4 d = m 2a dx . ( "+", .. ),


-7­
2/3 9 9 2 ( x ) = a x 4 / 3 = 4 4 , (D) = U, U ­ " "

x4/3. 0 S (0) = 0. , , I m 2e
3/ 2

2/3

I = CU

,

(6 )

C
C = A
0

42S e , A= . m 9 D2

, () ~ x4/3, (2) (3) ~ ­x­2/3, v ~ x2/3 E ~ ­x1/3. . 3. , () . () = 0, . , , , . " " , A ( . 1) ( ) 8 2 l A= , (7 ) 9 ra l ­ (. 2). , ra , l >> ra, .

, I(U), C, , , :
e C = m A .
2

(8 )

0

e/m / . . , , .


-8­ .
1

, , , (. 4).
2 I



3

1




2 3 0 B


B





.4. () (). 1. B < B; 2. B = B; 3. B > B. ­ , ­

, , .
FL = - e v в B ,

v (.5). , , . , . , , , (.4, 1). B (.4, 2). B > B . , , (.4, 3). , , , -


-9­ 2 . e/m. . (r, , z) (.5). v r va U FL z : B 12 mv a = eU (9 ) 2
.5 .

(, ).

L = m r в v z-. . , .. (L1z = 0). B .
L2 z = m v a ra , va (ra ­ ). , ( ). M = r в FL z:

& M z = rF = revr B = eBrr ,
& F = ev r B ­ , v r = r ­ -

. z-

Lz = L2 z - L1z = M z dt ,
0



­ . ,


- 10 ­
& mv a ra = eB rrdt = eB rdr ,
0 r ra

dr rdt = dt = dr . , & dt 1 mv a ra = eB ra2 2 r ­ . va (9) (10),

r ,

(

- r2 ,

)

(1 0 )


2

1 e 2 rk2 2 U= ra 1 - B . 8 m ra2 e 8U = m r B (1 - r 2 / r 2 ) a k a

(11)

[

]

2

(1 2 )

(r << r), (12) e 8U 2 2. (1 3 ) m ra B

, B U e/m.


. - 318. .6.


(.6): 1. 2. Mastech HY5005; . 3. Mastech HY30001; . 4. 7-38 5 . ( .6 );


1 .7. , , 7, 5. , : 4, -


- 11 ­ 3, 3 3 , 4 ­ 0-150 . 8 .
5

2

1

4

3

.6

.8, . 12 ( . 2 0 ). , , . : (+), (­). A . 0-2

0-3 3

, .8, 12 , . - mA 1, , .



V

0-300

.8 4,


- 12 ­ 1-2 . 0.2 . .
8

7 5


(6)

7

7


7




6

7

. .

1

2

3

4

.7
1. 0-150 2. =3 3. 4. 5 6 7 8 . . . .

. . . ( ) ( ) . . , .


- 13 ­ 1. " "


I(U) 0 100 10 . . , . . 1. U, I, U 3 /2 ,
3 /2



I(U) I(U 3/2). " " (6) , . C (6). , . , . (8) e/m, A. , A = 2.85. . , (7) . , (7) . , . . , () , ( .9), . , . , . 9 .9. " ", (.
. ­ .


- 14 ­ 1). A (7). 2.


U = 30, 40 50 I(I) 0...3 . . - , . ( , 5,6 .12), , ( 3,4 .12). 11. , . ( ), , . 12. , . 0 - 3 0,1 . (3 ) . , . , B ( ). , I , ( ) . 0-20 , , 10.


- 15 ­ . 2. B = kI. k , . , k 9.8 /.


Ia (). , . Ia () .11.
2. Ia .

U, 30 40 50

I, 0.1 0.2 ... 0.1

, ... ... ... ....

Ia ... ... ...

I, ....

B, .....

e/ m ....

e/m (12) ,
r
k a

0.45 5

r

, ra >> rk, (13). 2. e/m .


, Ia() , .4. , 10-20% , . . .9, 2 - z- 1 , , , . , . 10 , " : " .



- 16 ­
2.0 1.8 1.6

,

1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0



,

. 11. Ia . ­ U = ... .

-, , . , , , , . , , . , (. 10). , , " ", . , , , , (, 1 2 . 10). ( 1). . , .


- 17 ­ , , (.11). e/m , 1) (11) С , ( ); 2) ; 3) - , , . 1. .. . ., 21 , 2005, §34. 2. .. . . III . ., , 2006, § 101. 3. .. . -., 1956. , § 1. 4. . . . .. . ., , 1968, 75 112. 5. .. . . . . .. .. . ., - , 1987. 8. 6. Child C.D. Phys. Rev. Ser. I, 32, 492 (1911). 7. Langmuir I. Phys. Rev., Ser. II, 2, 450 (1913). 8. .. . . .-. - (), .3, 18 (1 9 2 4 ). 9. Langmuir I. and Blodgett K.B. Phys. Rev., 22, 4, 347 (1923). 1. ? 2. . . 3. . 4. ?


- 18 ­ 5. " " . 6. " " . 7. : ) ; ) ; ) . 8. . 9. . 10. (12) . 11. ? 12. e/m ) " " ) . 1. " 3/2" , (1) v (3) 2e 1 / 2 2 j = -v = - 0 (1 2 ) m U n , .. '(r) = n(r), 2e 1 / 2 2 = n 3/ 2 j . j = - n 3/ 2 0 m , n n3/2 (12) (1)-(3). , , I, U 3/2. , , . 2.
, ­ ­ r, ­ ­ ra. (1) (3), , , (4) , : I = - j ( r ) S ( r ) = -v 2rl = const , (1 4 ) l , S = 2rl ­ r. v (1), (2) (14), -


- 19 ­ , (x) a2 2 = , r a 2 =

(1 5 )

I m . z, 2 0 l 2e . (l >> ra) z, , (15) d a2 1d (r ) = . r dr dr r

() ~ x4/3, = rn. (15), An 2 r n -1 = a 2 A -1 / 2 r - n / 2 . (1 6 ) (16) r, r , (n - 1) = - n / 2 n = 2/3. n = 2/3 (16),

a2 9I m A = 2/3 = 8 l 2e . n 0 = r2/3 (15). (r) ~ ­r ­1/3, (5) ((r) 0) . , U. .. (ra) ­ (r) = U, (1 6 ) e 8 2 l C ra >> r C = A 0 , A = . 9 ra m , (5), (16), 8 2 l , 2 ­ r/r, A = 2 9 ra [3, 9]. I = CU
3/ 2

2/3

2/3

,


5

0-3

2


0.2m A 2m A

3.

1


2A

20 mA 0 .2A

000

00 0

000

00 0

1

2

3

4



3



0-150

- 20 -

.12 :
1. ; 2. ; 3. ; 4. ; 5. . 5. () 6. () 7. 8. 10. 11. 12. (­) (+) " " " "

(Mastech):
1. 2. 3. 4. () ()

7-38 1. U= ; 2. : 0.2