T. Okashita et al., Electromotive force generation due to electron and impurity cyclotron resonances in compound semiconductors, PHYSICA B, 302, 2001, pp. 369-373
We report on the resonant-photoelectromagnetic (R-PEM) effect in semiconduc
tor, that is the electromotive force generation associated with electron cy
clotron resonance (ECR) and impurity cyclotron resonance (ICR). This can be
explained with a model that the carriers excited by the resonant absorptio
n of the radiation induce the DC voltage through the thermomagnetic process
. In this study, we have applied this technique to the nInGaAs thin film an
d observed the negative voltage peak in addition to the usual positive ICR
one. From the temperature variation and the resonant magnetic field depende
nce of these signals, we have concluded that the negative signal is induced
by the ECR absorption. In addition, we have confirmed that the inversion o
f polarity for these signals originates in the inhomogeneous distribution o
f conduction electrons inside the film, and electrons localized at a fracti
on of the sample mainly cause the resonant absorption. Through the detailed
observation and analysis of the generated DC voltage, we can investigate t
he dynamics of hot carriers inhomogeneously excited in the sample by the EC
R as well as the TCR. Moreover, if we pay special attention to the polarity
of the generated voltage, we can determine the distribution of electrons a
nd impurities inside the film. (C) 2001 Elsevier Science B.V. All rights re
served.