Browsing by Author "Tan S.T."

Advances in the LED Materials and Architectures fro Energy-Saving Solid State Lighting towards Lighting Revolution

Tan S.T.; Sun, X. W.; Demir, Hilmi Volkan; DenBaars, S. P. (IEEE, 2012)

In this paper, we review the recent developments (in years 2010–2011) of energysaving solid-state lighting. The industry of white light-emitting diodes (LEDs) has made significant progress, and today, white LED market ...

Advantages of the Blue InGaN/GaN Light-Emitting Diodes with an AlGaN/GaN/AlGaN Quantum Well Structured Electron Blocking Layer

Ju, Z. G.; Liu W.; Zhang Z.-H.; Tan S.T.; Ji Y.; Kyaw, Z.; Zhang, X. L.; Lu, S. P.; Zhang, Y. P.; Zhu B.; Hasanov N.; Sun, X. W.; Demir, Hilmi Volkan (American Chemical Society, 2014-03-21)

InGaN/GaN light-emitting diodes (LEDs) with p-(AlGaN/GaN/AlGaN) quantum well structured electron blocking layer (QWEBL) are designed and grown by a metal− organic chemical-vapor deposition (MOCVD) system. The proposed QWEBL ...

Comparative study of field-dependent carrier dynamics and emission kinetics of InGaN/GaN light-emitting diodes grown on (11 2-2) semipolar versus (0001) polar planes

Ji Y.; Liu W.; Erdem, T.; Chen R.; Tan S.T.; Zhang Z.-H.; Ju, Z.; Zhang X.; Sun, H.; Sun, X. W.; Zhao Y.; DenBaars, S. P.; Nakamura, S.; Demir, Hilmi Volkan (AIP Publishing, 2014)

The characteristics of electroluminescence (EL) and photoluminescence (PL) emission from GaN light-emitting diodes (LEDs) grown on (11 (2) over bar2) semipolar plane and (0001) polar plane have been comparatively investigated. ...

Critical role of CdSe nanoplatelets in color-converting CdSe/ZnS nanocrystals for InGaN/GaN light-emitting diodes

Hasanov N.; Sharma, V. K.; Martinez, P. L. H.; Tan S.T.; Demir, Hilmi Volkan (OSA - The Optical Society, 2016)

Here we report CdSe nanoplatelets that are incorporated into color-converting CdSe/ZnS nanocrystals for InGaN/GaN light-emitting diodes. The critical role of CdSe nanoplatelets as an exciton donor for the color conversion ...

Decoupling contact and mirror: an effective way to improve the reflector for flip-chip InGaN/GaN-based light-emitting diodes

Zhu B.; Liu W.; Lu S.; Zhang, Y.; Hasanov N.; Zhang X.; Ji Y.; Zhang Z.-H.; Tan S.T.; Liu, H.; Demir, Hilmi Volkan (Institute of Physics Publishing, 2016)

In the conventional fabrication process of the widely-adopted Ni/Ag/Ti/Au reflector for InGaN/GaN-based flip-chip light-emitting diodes (LEDs), the contact and the mirror are entangled together with contrary processing ...

An efficient non-Lambertian organic light-emitting diode using imprinted submicron-size zinc oxide pillar arrays

Liu, S. W.; Wang, J. X.; Divayana, Y.; Dev, K.; Tan S.T.; Demir, Hilmi Volkan; Sun, X. W. (AIP, 2013)

We report phosphorescent organic light-emitting diodes with a substantially improved light outcoupling efficiency and a wider angular distribution through applying a layer of zinc oxide periodic nanopillar arrays by pattern ...

Enhanced hole transport in InGaN/GaN multiple quantum well light-emitting diodes with a p-type doped quantum barrier

Ji Y.; Zhang, Z. -H.; Tan S.T.; Ju, Z. G.; Kyaw, Z.; Hasanov N.; Liu W.; Sun X. W.; Demir, Hilmi Volkan (Optical Society of America, 2013)

We study hole transport behavior of InGaN/GaN light-emitting diodes with the dual wavelength emission method. It is found that at low injection levels, light emission is mainly from quantum wells near p-GaN, indicating ...

Facile synthesis of luminescent AgInS2–ZnS solid solution nanorods

Yang, X.; Tang, Y.; Tan S.T.; Bosman, M.; Dong, Z.; Leck K.S.; Ji Y.; Demir, Hilmi Volkan; Sun, X. W. (Wiley-VCH Verlag, 2013-04-16)

Highly luminescent semiconducting AgInS2–ZnS solid solution nanorods are successfully prepared by a facile one-pot solvothermal method. The resulting solid solution nanorods with length of 32 ± 5 nm are formed by fast ...

Full Visible Range Covering InP/ZnS Nanocrystals with High Photometric Performance and Their Application to White Quantum Dot Light-Emitting Diodes

Yang, X.; Zhao, D.; Leck K.S.; Tan S.T.; Tang, Y. X.; Zhao, J.; Demir, Hilmi Volkan; Sun, X. W. (Wiley-VCH Verlag, 2012-04-30)

High-quality InP/ZnS core–shell nanocrystals with luminescence tunable over the entire visible spectrum have been achieved by a facile one-pot solvothermal method. These nanocrystals exhibit high quantum yields (above 60%), ...

High brightness formamidinium lead bromide perovskite nanocrystal light emitting devices

Perumal, A.; Shendre, S.; Li, M.; Tay, Y. K. E.; Sharma, V. K.; Chen, S.; Wei, Z.; Liu, Q.; Gao, Y.; Buenconsejo, P. J. S.; Tan S.T.; Gan, C. L.; Xiong, Q.; Sum, T. C.; Demir, Hilmi Volkan (Nature Publishing Group, 2016)

Formamidinium lead halide (FAPbX3) has attracted greater attention and is more prominent recently in photovoltaic devices due to its broad absorption and higher thermal stability in comparison to more popular methylammonium ...

High-efficiency and low-loss gallium nitride dielectric metasurfaces for nanophotonics at visible wavelengths

Emani, N. K.; Khaidarov, E.; Paniagua-Domínguez, R.; Fu, Y. H.; Valuckas, V.; Lu S.; Zhang X.; Tan S.T.; Demir, Hilmi Volkan; Kuznetsov, A. I. (American Institute of Physics Inc., 2017)

The dielectric nanophotonics research community is currently exploring transparent material platforms (e.g., TiO2, Si3N4, and GaP) to realize compact high efficiency optical devices at visible wavelengths. Efficient ...

Highly Efficient Visible Colloidal Lead-Halide Perovskite Nanocrystal Light-Emitting Diodes

Yan, F.; Xing, J.; Xing, G.; Quan, L.; Tan S.T.; Zhao, J.; Su, R.; Zhang, L.; Chen, S.; Zhao Y.; Huan, A.; Sargent, E. H.; Xiong, Q.; Demir, Hilmi Volkan (American Chemical Society, 2018)

Lead-halide perovskites have been attracting attention for potential use in solid-state lighting. Following the footsteps of solar cells, the field of perovskite light-emitting diodes (PeLEDs) has been growing rapidly. ...

A hole modulator for InGaN/GaN light-emitting diodes

Zhang, Z-H.; Kyaw, Z.; Liu W.; Ji Y.; Wang, L.; Tan S.T.; Sun, X. W.; Demir, Hilmi Volkan (American Institute of Physics, 2015)

The low p-type doping efficiency of the p-GaN layer has severely limited the performance of InGaN/GaN light-emitting diodes (LEDs) due to the ineffective hole injection into the InGaN/GaN multiple quantum well (MQW) active ...

Improving hole injection efficiency by manipulating the hole transport mechanism through p-type electron blocking layer engineering

Zhang, Zi-Hui; Ju, Z.; Liu W.; Tan S.T.; Ji Y.; Kyaw, Z.; Zhang X.; Hasanov N.; Sun, X. W.; Demir, Hilmi Volkan (Optical Society of America, 2014)

The p-type AlGaN electron blocking layer (EBL) is widely used in InGaN/GaN light-emitting diodes (LEDs) for electron overflow suppression. However, a typical EBL also reduces the hole injection efficiency, because holes ...

Influence of n-type versus p-type AlGaN electron-blocking layer on InGaN/GaN multiple quantum wells light-emitting diodes

Ji Y.; Zhang Z.-H.; Kyaw, Z.; Tan S.T.; Ju, Z. G.; Zhang, X. L.; Liu W.; Sun, X. W.; Demir, Hilmi Volkan (AIP Publishing, 2013-08-01)

The effect of n-AlGaN versus p-AlGaN electron-blocking layers (EBLs) on the performance of InGaN/GaN light-emitting diodes is studied in this work. Experimental results suggest that the n-type EBL leads to higher optical ...

InGaN/GaN light-emitting diode with a polarization tunnel junction

Zhang Z.-H.; Tan S.T.; Kyaw, Z.; Ji Y.; Liu W.; Ju, Z.; Hasanov N.; Sun, X. W.; Demir, Hilmi Volkan (American Institute of Physics, 2013)

We report InGaN/GaN light-emitting diodes (LED) comprising in situ integrated p(+)-GaN/InGaN/n(+)-GaN polarization tunnel junctions. Improved current spreading and carrier tunneling probability were obtained in the proposed ...

InGaN/GaN multiple-quantum-well light-emitting diodes with a grading InN composition suppressing the Auger recombination

Zhang Z.-H.; Liu W.; Ju, Z.; Tan S.T.; Ji Y.; Kyaw, Z.; Zhang, X.; Wang, L.; Sun, X. W.; Demir, Hilmi Volkan (AIP Publishing, 2014)

In conventional InGaN/GaN light-emitting diodes (LEDs), thin InGaN quantum wells are usually adopted to mitigate the quantum confined Stark effect (QCSE), caused due to strong polarization induced electric field, through ...

Investigation of p-type depletion doping for InGaN/GaN-based light-emitting diodes

Zhang, Y.; Zhang Z.-H.; Tan S.T.; Hernandez-Martinez, P. L.; Zhu B.; Lu S.; Kang, X. J.; Sun, X. W.; Demir, Hilmi Volkan (American Institute of Physics Inc., 2017)

Due to the limitation of the hole injection, p-type doping is essential to improve the performance of InGaN/GaN multiple quantum well light-emitting diodes (LEDs). In this work, we propose and show a depletion-region ...

Light extraction efficiency enhancement of colloidal quantum dot light-emitting diodes using large-scale nanopillar arrays

Yang, X.; Dev, K.; Wang, J.; Mutlugun, E.; Dang, C.; Zhao Y.; Liu, S.; Tang, Y.; Tan S.T.; Sun, X. W.; Demir, Hilmi Volkan (Wiley-VCH Verlag, 2014)

A colloidal quantum dot light-emitting diode (QLED) is reported with substantially enhanced light extraction efficiency by applying a layer of large-scale, low-cost, periodic nanopillar arrays. Zinc oxide nanopillars are ...

Modulating ohmic contact through InGaxNyOz interfacial layer for high-performance InGaN/GaN-based light-emitting diodes

Zhu B.; Tan S.T.; Liu W.; Lu S.; Zhang, Y.; Chen, S.; Hasanov N.; Kang, X.; Demir, Hilmi Volkan (Institute of Electrical and Electronics Engineers Inc., 2016)

We report the improved performance of InGaN/GaN-based light-emitting diodes (LEDs) through the design and the formation of the InGaxNyOz interfacial layer, which maintains high reflectivity of silver and forms good ohmic ...