Open AccessСпектры остаточной фотопроводимости в гетероструктурах с квантовыми ямами HgTe/CdHgTe
Author(s) -
K. E. Spirin,
Д. М. Гапонова,
В. И. Гавриленко,
N. N. Mikhaĭlov,
С. А. Дворецкий
Publication year - 2019
Publication title -
fizika i tehnika poluprovodnikov
Language(s) - English
Resource type - Journals
eISSN - 1726-7315
pISSN - 0015-3222
DOI - 10.21883/ftp.2019.10.48297.43
Subject(s) - quantum well , photoconductivity , heterojunction , wavelength , optoelectronics , materials science , free carrier , electric field , optics , condensed matter physics , physics , laser , quantum mechanics
Spectra of persistent photoconductivity (PPC) in HgTe/CdHgTe quantum well (QW) heterostructures of both n- and p-types have been investigated at T = 4.2 K. PPC is shown to be either positive (increase of carrier concentration in QW) or negative depending on a wavelength of the illumination. As a general trend, PPC maxima in n-type sample correspond to PPC minima in p-type samples and vice versa. It is discovered that in p-type samples the illumination with certain wavelengths results in the freezing out of free carriers in QWs but not in the conversion of the conductivity type. The latter indicates a significant role in the PPC mechanism of the built-in electric field that is switching off at the QW neutralization.