@InProceedings{PenaPPSBOFRA:2016:ExInPh,
author = "Pena, Fernando Silva and Pirralho, Mar{\'{\i}}lia P{\'a}scoa
and Peres, Marcelos Lima and Soares, Demetrio Werner and Braga,
Paula Oliveira and Okasaki, Anderson Kenji and Fornari, Celso
Israel and Rappl, Paulo Henrique de Oliveira and Abramof,
Eduardo",
affiliation = "{Universidade Federal de Itajub{\'a} (UNIFEI)} and {Universidade
Federal de Itajub{\'a} (UNIFEI)} and {Universidade Federal de
Itajub{\'a} (UNIFEI)} and {Universidade Federal de Itajub{\'a}
(UNIFEI)} and {Universidade Federal de Itajub{\'a} (UNIFEI)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Experimental investigation of photoconductivity in n-type PbTe
quantum wells",
year = "2016",
organization = "Brazilian MRS Meeting, 15.",
abstract = "PbTe is a narrow gap semiconductor which exhibits interesting
properties that differentiate it from othersemiconductors [1].PbTe
based materials have being widely used in the fabrication of
infrared devices [2] and its electrical properties are well
investigated in literature. Concerning to photoconductivity
effect, very few information have being reported in structures
base in this compound. In this work, we present photoconductivity
measurements performed in n-type PbTe quantum wells (QW) under
infrared (IR) illumination and the results presented anomalous
behavior at different temperature regions. Remarkably, the
increasing of photoresponse reached 80 times the value measured
under dark conditions at 150K, for example.For temperatures below
250K, the effect of persistent photoconductivity was also
observed. In addition, a metal-insulator transition is observed in
the system as the temperature crosses the value of 200K,
approximately, indicating that there is transference of electrons
from the barriers into the QW.The PbTe/Pb1-xEuxTe QWs samples
investigated in this work weregrown by molecular beam epitaxy on
(111) cleaved BaF2substrates. The sample structure consisted of a
2 to 3 µmthick Pb1-xEuxTe buffer layer grown on top of the
(111)BaF2 substrate followed by a PbTe well embedded betweentwo
Pb1-xEuxTe barriers doped with bismuth, which guarantee an n-type
character for these samples.The width of the QWs are 14nm and
10nm. From the decay curves of the photoconductivity measurements,
it is possible to detect the presence of defect levels inside the
QWs. In order to obtain a detailed description of the transport
properties of the systems, Hall measurements were performed under
light and dark conditions. After a systematic analysis, we expect
to obtain a general description of the photoconductivity effect
observed in these QWs. The information obtained from this
investigation can be useful for the development or improvement of
devices based on PbTe compound.",
conference-location = "Campinas, SP",
conference-year = "25-29 Sept.",
language = "en",
urlaccessdate = "13 maio 2024"
}