Surface magneto-plasmons in magnetic multilayers - Walther ...
Surface magneto-plasmons in magnetic multilayers - Walther ...
Surface magneto-plasmons in magnetic multilayers - Walther ...
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Section 2.3<br />
Reflectivity of surface <strong>plasmons</strong> 19<br />
E(z) = Re −ik(i) z z ik<br />
+ Le (i)<br />
z z<br />
≡ A(z) + B(z). (2.38)<br />
R and L are constants <strong>in</strong> each layer. A(z) represents the amplitude of the right-<br />
travell<strong>in</strong>g and B(z) the amplitude of the left-travell<strong>in</strong>g wave. Further, as shown <strong>in</strong><br />
0 1 2<br />
n 0<br />
A 0<br />
B 0<br />
A ’<br />
1<br />
B ’<br />
1<br />
n 1<br />
d<br />
A 1<br />
B 1<br />
Figure 2.7: Illustration of the matrix method after Yeh [43]. Ai represents the amplitude<br />
of a right-travell<strong>in</strong>g wave and Bi of a left-travell<strong>in</strong>g wave on the left side of the<br />
<strong>in</strong>terface ij. And A ′ j and B′ j are the amplitudes of a right- and a left-travell<strong>in</strong>g<br />
wave on the right side of the <strong>in</strong>terface ij. ni is the complex refractive <strong>in</strong>dex of<br />
the medium i.<br />
Fig. 2.7, it is not only differentiated between right- and left-travell<strong>in</strong>g waves but also<br />
between waves on the right (with prime) and left (without prim) side of a given<br />
<strong>in</strong>terface. Regard<strong>in</strong>g A (′)<br />
i<br />
by a matrix.<br />
<br />
Ai<br />
Bi<br />
and B(′)<br />
i<br />
<br />
= ˆ D −1<br />
i ˆ Dj<br />
n 2<br />
A ’<br />
2<br />
B ’<br />
2<br />
x<br />
as column vectors, the amplitudes are connected<br />
<br />
A ′ j<br />
B ′ j<br />
<br />
≡ ˆ Dij<br />
where the ˆ Di are the so-called dynamical matrices given by<br />
Di =<br />
⎧⎛<br />
⎝<br />
⎪⎨<br />
⎛<br />
1 1<br />
√ ε (i) cos θi − √ ε (i) cos θi<br />
√ ε (i) − √ ε (i)<br />
⎞<br />
⎞<br />
z<br />
<br />
A ′ jB ′ <br />
j , (2.39)<br />
⎠ for s-polarised light<br />
⎝<br />
⎪⎩<br />
cos θi cos θi<br />
⎠ for p-polarised light .<br />
(2.40)