Towards a high-intensity muon source at CiADS

The proposal of a high-intensity muon source driven by the CiADS linac, which has the potential to be one of the state-of-the-art facilities, is presented in this paper. We briefly introduce the development progress of the superconducting linac of CiADS. Then the consideration of challenges related to the high-power muon production target is given and the liquid lithium jet muon production target concept is proposed, for the first time. The exploration of the optimal target geometry for surface muon production efficiency and the investigation into the performance of liquid lithium jet target in muon rate are given. Based on the comparison between the liquid lithium jet target and the rotation graphite target, from perspectives of surface muon production efficiency, heat processing ability and target geometry compactness, the advantages of the new target concept are demonstrated and described comprehensively. The technical challenges and the feasibility of the free-surface liquid lithium target are discussed

In-situ passivation perovskite targeting efficient light-emitting diodes via spontaneously formed silica network

Perovskite materials are attractive candidates as emitting layers in light-emitting diodes due to their excellent optical and electrical properties. Effective charge radiative recombination is a key to target high-efficiency perovskite light-emitting diodes (PeLEDs). State-of-the-art effective passivation chemicals in PeLEDs mostly belong to organic chelating molecules, associated with like molecular detachment in the device operation, which simultaneously degrades the performance especially the operational stability of the devices. Here, a silane material tetraethoxysilane (TEOS), which can be crosslinkable to avoid any likely detachment from perovskite film, is incorporated into the perovskite film to enhance film radiative recombination and stability. An oxo-bridged silica network anchored with perovskite is formed after the TEOS in-situ crosslinking process. It is found that the lone pair electrons in TEOS network can coordinate with the undercoordinated Pb2+ of perovskite. Consequently, defect states in perovskite film are dramatically diminished, which enhances radiative recombination. The photoluminescence intensity of resultant perovskite-TEOS film is enhanced by 40% over that of the pristine one. The average photoluminescence lifetime of perovskite-TEOS film reaches 58 ns, enhanced by 65% over that of the pristine perovskite film of 35 ns.. As a result, a green PeLED achieved an external quantum efficiency of 16.6% with improved working stability. This work presents a facile strategy targeting efficient and stable perovskite devices via utilizing detachment-free self-crosslinked ligands

Towards a high-intensity muon source

A high-intensity muon source driven by a continuous-wave superconducting linac holds the potential to significantly advance the intensity frontier of muon sources. Alongside advancements in accelerator technologies, breakthroughs in muon production target and collection schemes are essential. After a brief introduction to the development of the accelerator-driven system superconducting linac, a novel muon production target is proposed, utilizing a free-surface liquid lithium jet capable of handling the heat power generated by a proton beam with an energy of 600 MeV and a current of 5 mA. It is predicted by our simulation studies that the lithium target is more efficient in surface muon production compared to the rotating graphite target. The parameter space of the front end consisting of a lithium target and a large-aperture capture solenoid is explored, from the perspective of production efficiency, capture efficiency, and characteristics of the surface muon beam