Free carrier screening in coupled asymmetric GaN quantum discs
We present an investigation of free-carrier screening in coupled asymmetric GaN quantum discs with embedded AlGaN barriers using time-integrated and time-resolved micro-photoluminescence measurements, supported by three-dimensional multi-band k.p computational modeling. We observe that with increasi...
| Autori principali: | , , , , , , , |
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| Natura: | Conference item |
| Pubblicazione: |
2006
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| _version_ | 1826285400478449664 |
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| author | Lee, K Na, J Birner, S Taylor, R Yi, SN Park, Y Park, C Kang, T |
| author_facet | Lee, K Na, J Birner, S Taylor, R Yi, SN Park, Y Park, C Kang, T |
| author_sort | Lee, K |
| collection | OXFORD |
| description | We present an investigation of free-carrier screening in coupled asymmetric GaN quantum discs with embedded AlGaN barriers using time-integrated and time-resolved micro-photoluminescence measurements, supported by three-dimensional multi-band k.p computational modeling. We observe that with increasing optical excitation the carrier lifetime decreases and emission energy blue-shifts. This originates from the screening of built-in piezo- and pyroelectric fields in the quantum discs by photo-generated free-carriers. Due to non-resonant tunneling of carriers from the smaller disc to the larger disc, free carrier screening is enhanced in the larger disc. The non-resonant tunneling was found to have a significant role in samples with a thin barrier, as the screening decreased with barrier thickness (i.e. decreased tunneling). Computational modeling, was in good agreement with the experimental results. |
| first_indexed | 2024-03-07T01:28:15Z |
| format | Conference item |
| id | oxford-uuid:92b5153c-032c-45be-821a-133e19c90cbb |
| institution | University of Oxford |
| last_indexed | 2024-03-07T01:28:15Z |
| publishDate | 2006 |
| record_format | dspace |
| spelling | oxford-uuid:92b5153c-032c-45be-821a-133e19c90cbb2022-03-26T23:27:30ZFree carrier screening in coupled asymmetric GaN quantum discsConference itemhttp://purl.org/coar/resource_type/c_5794uuid:92b5153c-032c-45be-821a-133e19c90cbbSymplectic Elements at Oxford2006Lee, KNa, JBirner, STaylor, RYi, SNPark, YPark, CKang, TWe present an investigation of free-carrier screening in coupled asymmetric GaN quantum discs with embedded AlGaN barriers using time-integrated and time-resolved micro-photoluminescence measurements, supported by three-dimensional multi-band k.p computational modeling. We observe that with increasing optical excitation the carrier lifetime decreases and emission energy blue-shifts. This originates from the screening of built-in piezo- and pyroelectric fields in the quantum discs by photo-generated free-carriers. Due to non-resonant tunneling of carriers from the smaller disc to the larger disc, free carrier screening is enhanced in the larger disc. The non-resonant tunneling was found to have a significant role in samples with a thin barrier, as the screening decreased with barrier thickness (i.e. decreased tunneling). Computational modeling, was in good agreement with the experimental results. |
| spellingShingle | Lee, K Na, J Birner, S Taylor, R Yi, SN Park, Y Park, C Kang, T Free carrier screening in coupled asymmetric GaN quantum discs |
| title | Free carrier screening in coupled asymmetric GaN quantum discs |
| title_full | Free carrier screening in coupled asymmetric GaN quantum discs |
| title_fullStr | Free carrier screening in coupled asymmetric GaN quantum discs |
| title_full_unstemmed | Free carrier screening in coupled asymmetric GaN quantum discs |
| title_short | Free carrier screening in coupled asymmetric GaN quantum discs |
| title_sort | free carrier screening in coupled asymmetric gan quantum discs |
| work_keys_str_mv | AT leek freecarrierscreeningincoupledasymmetricganquantumdiscs AT naj freecarrierscreeningincoupledasymmetricganquantumdiscs AT birners freecarrierscreeningincoupledasymmetricganquantumdiscs AT taylorr freecarrierscreeningincoupledasymmetricganquantumdiscs AT yisn freecarrierscreeningincoupledasymmetricganquantumdiscs AT parky freecarrierscreeningincoupledasymmetricganquantumdiscs AT parkc freecarrierscreeningincoupledasymmetricganquantumdiscs AT kangt freecarrierscreeningincoupledasymmetricganquantumdiscs |