Nanocrystal integrated light emitting diodes based on radiative and nonradiative energy transfer for the green gap
Demir, Hilmi Volkan
2009 IEEE LEOS Annual Meeting Conference Proceedings
75 - 76
Item Usage Stats
MetadataShow full item record
Recently the photometric conditions for ultra-efficient solid-state lighting have been discussed [1-2]. These studies show that a luminous efficacy of optical radiation at 408 lm/Wopt and a color rendering index (CRI) of 90 at a correlated color temperature (CCT) of 3000 K are achievable at the same time. For this purpose light emitting diodes (LEDs) emitting in blue, green, yellow, and red colors at 463, 530, 573, and 614 nm with relative optical power levels of 1/8, 2/8, 2/8, and 3/8, are required, respectively [1-2]. Although InxGa1-xN material system is capable to cover the whole visible by changing the In composition (x), it is technically extremely challenging to obtain efficient green/yellow light emitting diodes especially at those wavelengths (i.e., at 530 nm and 573 nm, respectively) due to reduced internal quantum efficiency [2-4]. Furthermore, by using the (Al xGa1-x)1-yInyP quaternary alloy it is also possible to cover from 650 nm to 580 nm. However, the efficiencies significantly decrease towards green. Therefore, there exists a significant gap in the green-yellow spectral regions (known as "the green gap") to make efficient light emitting diodes. To address this green gap problem, we propose and demonstrate proof-of-concept nanocrystal (NCs) hybridized green/yellow light emitting diodes that rely on both radiative energy transfer and nonradiative energy transfer (i.e., FRET-Förster resonance energy transfer) for color conversion on near-ultraviolet (near-UV) LEDs.
Color rendering index
Correlated color temperature
Green-yellow spectral region
Internal quantum efficiency
Nonradiative energy transfer
Proof of concept
Radiative energy transfer
Resonance energy transfer
Solid state lighting
Light emitting diodes
Published Version (Please cite this version)http://dx.doi.org/10.1109/LEOS.2009.5343463
Showing items related by title, author, creator and subject.
Non-radiative resonance energy transfer in bi-polymer nanoparticles of fluorescent conjugated polymers Ozel I.O.; Ozel, T.; Demir, Hilmi Volkan; Tuncel, D. (Optical Society of American (OSA), 2010)This work demonstrates the comparative studies of non-radiative resonance energy transfer in bi-polymer nanoparticles based on fluorescent conjugated polymers. For this purpose, poly[(9,9-dihexylfluorene) (PF) as a donor ...
Synthesis of symmetrical multichromophoric bodipy dyes and their facile transformation into energy transfer cassettes Bozdemir, O. A.; Cakmak, Y.; Sozmen F.; Ozdemir, T.; Siemiarczuk, A.; Akkaya, E. U. (2010)Multichromophoric boron-dipyrromethene (Bodipy) dyes synthesized on phenylene-ethynylene platforms have been be converted to energy transfer cassettes in a one-step chemical transformation. Excitation energy transfer ...
Ta V.D.; Yang, S.; Wang, Y.; Gao, Y.; He, T.; Chen, R.; Demir, Hilmi Volkan; Sun H. (American Institute of Physics Inc., 2015)This work demonstrates mass production of printable multi-color lasing microarrays based on uniform hemispherical microcavities on a distributed Bragg reflector using inkjet technique. By embedding two different organic ...