Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2006.
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| Format: | Thesis |
| Language: | eng |
| Published: |
Massachusetts Institute of Technology
2007
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| Online Access: | http://hdl.handle.net/1721.1/36120 |
| _version_ | 1811086190805254144 |
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| author | Rivoire, Kelley (Kelley E.) |
| author2 | Marc A. Baldo. |
| author_facet | Marc A. Baldo. Rivoire, Kelley (Kelley E.) |
| author_sort | Rivoire, Kelley (Kelley E.) |
| collection | MIT |
| description | Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2006. |
| first_indexed | 2024-09-23T13:22:14Z |
| format | Thesis |
| id | mit-1721.1/36120 |
| institution | Massachusetts Institute of Technology |
| language | eng |
| last_indexed | 2024-09-23T13:22:14Z |
| publishDate | 2007 |
| publisher | Massachusetts Institute of Technology |
| record_format | dspace |
| spelling | mit-1721.1/361202019-04-10T10:31:46Z Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states Rivoire, Kelley (Kelley E.) Marc A. Baldo. Massachusetts Institute of Technology. Dept. of Physics. Massachusetts Institute of Technology. Dept. of Physics. Physics. Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2006. Includes bibliographical references (p. 59-63). In this thesis, the possibility of enhancing the efficiency of small molecule organic light-emitting diodes through spin-orbit effects is examined. Because only singlet spin states, statistically one quarter of the total possible states, emit fluorescent light, it has generally been thought that a maximum of 25% efficiency could be attained without the addition of an emissive phosphor. Here, we present evidence that this is not a fundamental limit. Two OLED structures have been studied, each providing evidence that the efficiency of the OLED can be enhanced by the use of a heavy-metal material to mix spin in charge-transfer states. A structure with a heavy-metal mixing layer placed beside a neat emissive layer was found to show a (2.5 ± 0.3) times enhancement in the efficiency compared with an OLED without the heavy-metal layer. However, differences in the electroluminescent emission spectra made attributing this result to spin statistics alone difficult. In a structure with the the heavy-metal mixing layer placed next to a fluorescent dye doped into a host, a (2.7 ± 0.2) times enhancement in the efficiency is measured. by Kelley Rivoire. S.B. 2007-02-21T11:28:45Z 2007-02-21T11:28:45Z 2006 2006 Thesis http://hdl.handle.net/1721.1/36120 71844614 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 63 p. application/pdf Massachusetts Institute of Technology |
| spellingShingle | Physics. Rivoire, Kelley (Kelley E.) Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states |
| title | Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states |
| title_full | Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states |
| title_fullStr | Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states |
| title_full_unstemmed | Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states |
| title_short | Enhancing the efficiency of organic LEDs through spin-orbit coupling of charge-transfer states |
| title_sort | enhancing the efficiency of organic leds through spin orbit coupling of charge transfer states |
| topic | Physics. |
| url | http://hdl.handle.net/1721.1/36120 |
| work_keys_str_mv | AT rivoirekelleykelleye enhancingtheefficiencyoforganicledsthroughspinorbitcouplingofchargetransferstates |