The present invention provides a heterocyclic compound and an organic light-emitting device including the heterocyclic compound. The organic light-emitting devices using the heterocyclic compounds have high-efficiency, low driving voltage, high luminance and long lifespan.

Organic light-emitting device

For in vivo imaging, the short-wavelength infrared region (SWIR; 1000–2000 nm) provides several advantages over the visible and near-infrared regions: general lack of autofluorescence, low light absorption by blood and tissue, and reduced scattering. However, the lack of versatile and functional SWIR emitters has prevented the general adoption of SWIR imaging by the biomedical research community. Here, we introduce a class of high-quality SWIR-emissive indium-arsenide-based quantum dots (QDs) that are readily modifiable for various functional imaging applications, and that exhibit narrow and size-tunable emission and a dramatically higher emission quantum yield than previously described SWIR probes. To demonstrate the unprecedented combination of deep penetration, high spatial resolution, multicolor imaging and fast-acquisition-speed afforded by the SWIR QDs, we quantified, in mice, the metabolic turnover rates of lipoproteins in several organs simultaneously and in real time as well as heartbeat and breathing rates in awake and unrestrained animals, and generated detailed three-dimensional quantitative flow maps of the mouse brain vasculature.

Next-generation in vivo optical imaging with short-wave infrared quantum dots

Organic photodetectors (OPDs) with a performance comparable to that of conventional inorganic ones have recently been demonstrated for the visible regime. However, near-infrared photodetection has proven to be challenging and, to date, the true potential of organic semiconductors in this spectral range (800-2500 nm) remains largely unexplored. In this work, it is shown that the main factor limiting the specific detectivity (D*) is non-radiative recombination, which is also known to be the main contributor to open-circuit voltage losses. The relation between open-circuit voltage, dark current, and noise current is demonstrated using four bulk-heterojunction devices based on narrow-gap donor polymers. Their maximum achievable D* is calculated alongside a large set of devices to demonstrate an intrinsic upper limit of D* as a function of the optical gap. It is concluded that OPDs have the potential to be a useful technology up to 2000 nm, given that high external quantum efficiencies can be maintained at these low photon energies.

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Intrinsic Detectivity Limits of Organic Near‐Infrared Photodetectors

Organic photodetectors have promising applications in low-cost imaging, health monitoring and near-infrared sensing. Recent research on organic photodetectors based on donor–acceptor systems has resulted in narrow-band, flexible and biocompatible devices, of which the best reach external photovoltaic quantum efficiencies approaching 100%. However, the high noise spectral density of these devices limits their specific detectivity to around 1013 Jones in the visible and several orders of magnitude lower in the near-infrared, severely reducing performance. Here, we show that the shot noise, proportional to the dark current, dominates the noise spectral density, demanding a comprehensive understanding of the dark current. We demonstrate that, in addition to the intrinsic saturation current generated via charge-transfer states, dark current contains a major contribution from trap-assisted generated charges and decreases systematically with decreasing concentration of traps. By modeling the dark current of several donor–acceptor systems, we reveal the interplay between traps and charge-transfer states as source of dark current and show that traps dominate the generation processes, thus being the main limiting factor of organic photodetectors detectivity. The suppression of dark current in organic photodetectors (OPDs) is important for maximizing the performance of the devices. Here, the authors report the relationship between the high dark saturation current and the presence of mid-gap trap states in OPDs with a donor–acceptor structure.

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Reverse dark current in organic photodetectors and the major role of traps as source of noise.

An organic photoelectronic device includes an anode and a cathode facing each other, and an organic layer between the anode and the cathode, the organic layer including a compound represented by Chemical Formula 1 as a visible light-absorbing body, and at least one of a hole buffer material having an energy bandgap of greater than or equal to about 2.8 eV and a HOMO level between a work function of the anode and a HOMO level of the compound represented by the Chemical Formula 1, and an electron buffer material having an energy bandgap of greater than or equal to about 2.8 eV and a LUMO level between a work function of the cathode and a LUMO level of the compound represented by the Chemical Formula 1.

Organic photoelectronic device and image sensor

Author(s): Wu, Zhenghui; Li, Ning; Eedugurala, Naresh; Azoulay, Jason D; Leem, Dong-Seok; Ng, Tse Nga | Abstract: AbstractTo achieve high detectivity in infrared detectors, it is critical to reduce the device noise. However, for non-crystalline semiconductors, an essential framework is missing to understand and predict the effects of disorder on the dark current. This report presents experimental and modeling studies on the noise current in exemplar organic bulk heterojunction photodiodes, with 10 donor–acceptor combinations spanning wavelength between 800 and 1600 nm. A significant reduction of the noise and higher detectivity were found in devices using non-fullerene acceptors (NFAs) in comparison to those using fullerene derivatives. The low noise in NFA blends was attributed to a sharp drop off in the distribution of bandtail states, as revealed by variable-temperature density-of-states measurements. Taking disorder into account, we developed a general physical model to explain the dependence of thermal noise on the effective bandgap and bandtail spread. The model provides theoretical targets for the maximum detectivity that can be obtained at different detection wavelengths in inherently disordered infrared photodiodes.

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Noise and detectivity limits in organic shortwave infrared photodiodes with low disorder

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Organic Upconversion Imager With Dual Electronic and Optical Readouts for Shortwave Infrared Light Detection

An organic photoelectric material may include a compound represented by the above Chemical Formula 1, and an organic photoelectric device and an image sensor including the organic photoelectric material.

Organic photoelectric material and organic photoelectric device and image sensor

According to example embodiments, a transmissive electrode may include a light transmission layer. The light transmission layer may include a metal and a metal oxide that is included in a smaller amount than the metal. According to example embodiments, an organic photoelectric device, as well as an image sensor, may include the transmissive electrode.

Light transmissive electrode, organic photoelectric device, and image sensor

The invention provides an organic photoelectric material, an organic photoelectronic device and an image sensor. The organic photoelectric material may include a compound represented by the above Chemical Formula 1, wherein A is a thiophene-containing aromatic group including 4 to 7 rings fused to one another, and an organic photoelectric device and an image sensor including the organic photoelectric material.

Dong Seok Leem

Papers

Noise and detectivity limits in organic shortwave infrared photodiodes with low disorder

Organic Upconversion Imager With Dual Electronic and Optical Readouts for Shortwave Infrared Light Detection

Organic photoelectric material and organic photoelectric device and image sensor

Light transmissive electrode, organic photoelectric device, and image sensor

Organic photoelectric material, organic photoelectronic device and image sensor