RESUMO
For the practical application of triplet-triplet annihilation-based photon upconversion (TTA-UC), the development of rigid, transparent, air-stable, and moldable materials with a high TTA-UC efficiency remains a challenging issue. In addition to the noncovalent introduction of ionic liquid emitters into the epoxy network, we covalently introduce emitters with polymerization sites to increase the emitter concentration to 35.6 wt %. A TTA-UC quantum yield ΦUC of 5.7% (theoretical maximum: 50%) or a TTA-UC efficiency ηUC of 11.4% (theoretical maximum: 100%) is achieved, which is the highest value ever achieved for a rigid polymer material. More importantly, the high emitter concentration speeds up the triplet diffusion and suppresses the back energy transfer from the emitter to sensitizer so that the sensitized emitter triplet can be effectively utilized for TTA. The generality of our finding is also confirmed for epoxy resins of similar emitter unit concentrations without the ionic liquid. This work provides important design guidelines for achieving highly efficient TTA-UC in rigid solid materials, which has been very difficult to achieve in the past. Furthermore, the solid-state TTA-UC exhibits high air stability, reflecting the high oxygen barrier performance of epoxy resins. The high moldability of epoxy resins allows the construction of upconversion materials with complex geometries at nano- to macroscopic scales.
RESUMO
It remains challenging to achieve efficient and air-stable photon upconversion (UC) in rigid, technologically valuable transparent films. Here, we report the first example of epoxy resins that show an air-stable and efficient triplet-triplet annihilation (TTA)-based UC. Epoxy resins are thermally cross-linked polymers widely used as coating and sealing materials in actual devices. To achieve efficient TTA-UC in rigid epoxy films, it is essential to execute both the triplet sensitization and triplet exciton diffusion processes without relying on molecular diffusion. This requires homogeneously dispersing emitter molecules without aggregation in three-dimensionally cross-linked rigid polymer networks at a high concentration (ca. 1000 mM) such that the inter-emitter distance is less than 1 nm, where dexter energy transfer can occur. This difficult requirement is solved by employing an ionic liquid emitter that consists of 9,10-diphenylanthracene sulfonate and lipophilic phosphonium ions bearing long alkyl chains. The obtained epoxy resins show a high TTA-UC efficiency (ηUC = 3.8%) and low threshold excitation intensity (Ith = 40 mW cm-2) in air. These UC parameters are achieved by virtue of a very high sensitizer-to-emitter triplet energy-transfer efficiency (92.8%) and a significantly long emitter triplet lifetime (17.8 ms) that reflect the high emitter concentration and the rigid chromophore environment, respectively. The bulk transparent upconverting resins can be prepared in air and function in air, which opens a new avenue toward a wide range of real-world applications.
RESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
To reduce the ever-increasing energy consumption in datacenters, one of the effective approaches is to increase the ambient temperature, thus lowering the energy consumed in the cooling systems. However, this entails more stringent requirements for the reliability and durability of the optoelectronic components. Herein, we fabricate and demonstrate silicon-polymer hybrid modulators which support ultra-fast single-lane data rates up to 200 gigabits per second, and meanwhile feature excellent reliability with an exceptional signal fidelity retained at extremely-high ambient temperatures up to 110 °C and even after long-term exposure to high temperatures. This is achieved by taking advantage of the high electro-optic (EO) activities (in-device n3r33 = 1021 pm V-1), low dielectric constant, low propagation loss (α, 0.22 dB mm-1), and ultra-high glass transition temperature (Tg, 172 °C) of the developed side-chain EO polymers. The presented modulator simultaneously fulfils the requirements of bandwidth, EO efficiency, and thermal stability for EO modulators. It could provide ultra-fast and reliable interconnects for energy-hungry and harsh-environment applications such as datacentres, 5G/B5G, autonomous driving, and aviation systems, effectively addressing the energy consumption issue for the next-generation optical communication.
RESUMO
In this work, 1 GHz video data was collected by a CMOS camera and successfully transmitted by the electro-optic (EO) modulator driven by an external modulation module integrated onto the same chip. For this application, the EO modulator component included a polymer waveguide modulator, which performed a 20 GHz bandwidth, clear eye diagram opening with a Q factor of 10.3 at 32 Gbit/s and a drive voltage of 1.5 Vpp. By utilizing a thermally stable EO polymer, the wide-band polymer modular can yield a photonic integrated camera sensor system which is a reliable processing platform for real-time data processing.
RESUMO
An electro-optic (EO) polymer waveguide using an ultra-thin silicon hybrid has been designed and fabricated. The silicon core has the thickness of 50 nm and a width of 5 µm. The waveguide was completed after covering the cladding with the high temperature stable EO polymer. We have demonstrated a low half-wavelength voltage of 0.9 V at the wavelength of 1.55 µm by using a Mach-Zehnder interference modulator with TM mode operation. The measured modulation corresponded to an effective in-device EO coefficient of 165 pm/V. By utilizing the traveling-wave electrode on the modulator the high-frequency response was tested up to 40 GHz. The 3 dB modulation bandwidth was measured to be 23 GHz. In addition, the high frequency sideband spectral measurement revealed that a linear response of the modulation index against the RF power was confirmed up to 40 GHz signal.