Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA.
Nat Commun. 2012;3:1005. doi: 10.1038/ncomms1985.
Optical antennas can control the emission from quantum emitters by modifying the local density of optical states via the Purcell effect. A variety of nanometallic antennas have been implemented to enhance and control key photoluminescence properties, such as the decay rate, directionality and polarization. However, their implementation in active devices has been hampered by the need to precisely place emitters near an antenna and to efficiently excite them electrically. Here we illustrate a design methodology for antenna electrodes that for the first time facilitates simultaneous operation as electrodes for current injection and as antennas capable of optically manipulating the electroluminescence. We show that by confining the electrically excited carriers to the vicinity of antenna electrodes and maximizing the optical coupling of the emission to a single, well-defined antenna mode, their electroluminescence can be effectively controlled. This work spurs the development of densely integrated, electrically driven light sources with tailored emission properties.
光学天线可以通过 Purcell 效应改变局域光态密度来控制量子发射器的发射。已经实现了各种纳米金属天线来增强和控制关键的光致发光特性,例如衰减率、方向性和偏振。然而,由于需要将发射器精确地放置在天线附近并有效地对其进行电激发,因此它们在有源器件中的应用受到了阻碍。在这里,我们展示了一种天线电极的设计方法,该方法首次实现了作为电流注入电极和作为能够光学操纵电致发光的天线的双重功能。我们表明,通过将电激发的载流子限制在天线电极附近,并使发射的光与单个明确的天线模式的耦合最大化,可以有效地控制它们的电致发光。这项工作推动了具有定制发射特性的密集集成、电驱动光源的发展。