Simultaneous enhancement of light extraction and spontaneous emission using a partially reflecting metasurface cavity

Abstract

The enhancement of the power conversion efficiency (PCE), and subsequent reduction of cost, of light emitting diodes (LEDs) is of crucial importance in the current lightening market. For this reason, we propose here a PCE-enhanced LED architecture, based on a partially-reflecting metasurface cavity (PRMC) structure. This structure simultaneously enhances the light extraction efficiency (LEE) and the spontaneous emission rate (SER) of the LED by enforcing the emitted light to radiate perpendicularly to the device, so as to suppress wave trapping and enhance field confinement near the emitter, while ensuring cavity resonance matching and maximal constructive field interference. The PRMC structure is designed using a recent surface susceptibility metasurface synthesis technique. A PRMC blue LED design is presented and demonstrated by full-wave simulation to provide LEE and SER enhancements by factors 4.0 and 1.9, respectively, which correspond to PCE enhancement factors of 6.2, 5.2 and 4.5 for IQEs of 0.25, 0.5 and 0.75, respectively, suggesting that the PRMC concept has a promising potential in LED technology. 7, 948-957 (2013). 14. D. Lu, J. J. Kan, E. E. Fullerton, and Z. Liu, "Enhancing spontaneous emission rates of molecules using nanopatterned multilayer hyperbolic metamaterials," Nat. Nanotechnol. 9, 48-53 (2014). 15. L. Ferrari, D. Lu, D. Lepage, and Z. Liu, "Enhanced spontaneous emission inside hyperbolic metamaterials,"

Design, concepts, and applications of electromagnetic metasurfaces

“…In the order of appearance, we present our work on birefringent transformations [98,122], bianisotropic refraction [123], light emission enhancement [124], remote spatial processing [125], and nonlinear second-harmonic generation (SHG) [96]. The reader is also referred to our related works on nonreciprocal nongyrotropic isolators [126], dielectric metasurfaces for dispersion engineering [127], and radiation pressure control [128].…”

“…[124] a partially reflecting metasurface cavity (PRMC) increasing the emission of photon sources in layered semiconductor structures using the susceptibility-GSTC technique presented in this paper. This PRMC simultaneously enhances the light extraction efficiency (LEE), spontaneous Figure 13.…”

Simultaneous Control of the Spatial and Temporal Spectra of Light With Space-Time Varying Metasurfaces

“…where ./ is the array division operator, whose resulting z component is the ratio of the z component of the numerator to the z component of the denominator, and y component is the ratio of the y component of the numerator to the y component of the denominator, while the zy and yz components are zero. Equations (8) can be easily generalized to the most general bianisotropic case by using (4) instead of (7). However, Eq.…”

“…where ζ 0 = T 0 /4 and τ = 3T 0 , corresponding to a pulse with temporal width T 0 . The time-varying susceptibilities, computed by (8), are plotted in Fig. 6.…”

Wave Scattering by a Cylindrical Metasurface Cavity of Arbitrary Cross Section: Theory and Applications

“…and B are found upon inserting these relations into the GSTCs (8) with(9), which yieldsE 1z − E 2z = −iωµ 0 χ tt mm H 1φ + H 2φ 2 , (B.3a) H 1φ − H 2φ = 0. (B.3b) Inserting (B.1) and (B.2) into (B.3), and simplifying, yields then…”