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Fig.1. CDS oscillations in a strong magnetic field
B=5 T
Fig.2. CDS oscillations in a strong magnetic field
(B=2 Tl) with parabolic and non-parabolic
dispersion laws.
Let us consider the change in the frequency of absorbed light and the band gap for a non-
quadratic dispersion law in the presence of a magnetic field. The sum over N in (1) and (2) extends
to all values of N for which the subradical expressions are not negative. Those values of ω, N, and B
for which the subradical expression in (1) and (2) is equal to zero determine the singular points of
the absorption coefficient. These points meet the condition:
max
(2
1)
(2)
g
r
E
N
H
2
max
1
4
(
)
(3)
2
g
g
c
E
E N
Where ω
max
is the frequency of the absorbed light corresponding to the absorption maximum.
Figures 3 and 4 show the changes in the maximum frequency of absorbed light in the presence of a
magnetic field.
It can be seen from (2) that for a given N, the absorbed light frequencies ωmax depend linearly
on the magnetic field, and from (3) we find that the maximum absorbed light frequency depends
nonlinearly on the magnetic field at different Landau levels. From Fig.4 we see that as the number
of Landau levels increases, the nonlinearity ωmax increases.
Figure 5a shows the changes in the maximum energy of an absorbed photon from a strong
magnetic field in InSb [12]. In these works, direct interband magneto-optical transitions were
observed in InSb at liquid helium temperature using magnetic fields up to 96.5 kOe. Hence, it is
possible to calculate the dependence of the maximum energy of the absorbed photon on the strong
magnetic field in InSb using formula (13). As a result, we obtain the dependence of the absorbed
photon energy on the magnetic field with a non-parabolic dispersion law in InSb (Fig. 5b). These
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