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In this paper we explore energy loss in the novel plasmonic PHOLED device architecture that enables next‐generation OLED operation by harnessing energy previously believed to be trapped in the plasmon mode. We determine that the quality of Ag used in the plasmon out‐coupling scheme can increase the device efficiency by greater than 30%. We identify the Ag adhesion layer as a way to tune the quality of Ag and discuss the effects on both plasmon in‐ and out‐coupling efficiencies. [ABSTRACT FROM AUTHOR]

In this paper we introduce a new light emitting device where phosphorescent emitters are intentionally coupled to the surface plasmon mode of the cathode. This achieves a decay rate enhancement and with subsequent conversion of the energy to photons in free space, we realize net gains in efficiency and stability. [ABSTRACT FROM AUTHOR]

Until recently, organic light emitting devices (OLEDs) have operated under the paradigm that the surface plasmon mode of contacts is lossy and should be avoided. We proposed and demonstrated a phosphorescent light emitting device (PHOLED) which intentionally couples the emissive exciton to the plasmon mode of a nearby metal contact to reduce the excited state lifetime [1]. This, in turn, reduces the steady state exciton density and the likelihood of destabilizing excited state interactions. We further demonstrated that a nanoparticle‐based outcoupling scheme extracts the energy coupled to the plasmon mode into air. In this paper, we demonstrate that the plasmon based PHOLED can exceed the efficiency of a conventional PHOLED while simultaneously increasing the stability. [ABSTRACT FROM AUTHOR]

Organic light‐emitting devices (OLEDs) are widely used for mobile displays, but the relatively short lifetime of blue OLEDs remains a challenge in many applications. Typically, instability is viewed as a material‐specific chemical degradation problem. It is known to be alleviated by reducing the operating current or otherwise decreasing the exciton density. It is shown here that this view is incomplete. For archetypical phosphorescent materials, it is observed that the dependence of photostability on the triplet exciton lifetime follows a cubic power law, steeper than its dependence on exciton density. It is demonstrated that the triplet exciton lifetime not only determines the energy stored within an OLED, it also determines the loss in luminescence by controlling the yield of quenching by defects. The dominant role of the triplet exciton lifetime suggests that the stability of the best OLED materials can be significantly improved via rapid extraction of the energy stored in triplet excitons. [ABSTRACT FROM AUTHOR]