Observation of Emission Enhancement Caused by Symmetric Carrier Depletion in III-V Nanomembrane Heterostructures

Autor(es)

Bernardes Marcal, Lucas Atila ^[1] ; Teixeira Rosa, Barbara Luiza ^{[1, 2]} ; Safar, Gustavo A. M. ^[1] ; Freitas, Raul O. ^[3] ; Schmidt, Oliver G. ^[4] ; Soares Guimaraes, Paulo Sergio ^{[1, 2]} ; Deneke, Christoph ^{[4, 5]} ; Malachias, Angelo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Minas Gerais, Dept Fis, BR-31270901 Belo Horizonte, MG - Brazil

^[2] DISSE Inst Nacl Ciencia & Tecnol Nanodisposit Sem, Rio De Janeiro - Brazil

^[3] Lab Nacl Luz Sincrotron, BR-13083100 Campinas, SP - Brazil

^[4] IFW Dresden, Dresden - Germany

^[5] Lab Nacl Nanotecnol LNNano CNPEM, BR-13083100 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ACS PHOTONICS; v. 1, n. 9, p. 863-870, SEP 2014.
• Citações Web of Science: 5

Resumo

Semiconductor nanomembranes are promising systems for many applications, since the band structure of a given material can be tailored to achieve specific configurations, which are not feasible by conventional growth procedures on rigid substrates. Here we show that optically active III-V membranes containing In As quantum dots exhibit a pronounced photoluminescence enhancement with respect to equivalent systems grown on top of flat substrates. The effect is explained by the formation of carrier depletion regions symmetrically located with respect to the optically active layer. This leads to the filling of excited states of the quantum dots and the overall spectra are enhanced at higher energies. Changes on the strain field that are expected to lead to a red-shift of the quantum dot emission play a reduced role in the final emission spectra in comparison with the depletion effects. These effects can be considered as another degree of freedom and a key ingredient for band engineering of extremely thin semiconductor membranes. (AU)

• Processo FAPESP: 11/22945-1 - Crescimento epitaxial sobre membranas semicondutoras auto-suportadas
• Beneficiário: Christoph Friedrich Deneke
• Modalidade de apoio: Auxílio à Pesquisa - Regular