Exciton polaritons are hybrid light-matter quantum states arising from strong coupling, offering a unique platform for exploring macroscopic quantum phenomena. However, how the coherence of external driving laser field is transferred to polaritons has remained an open question. Recently, the team of Prof. Jian Wu at East China Normal University achieved a critical breakthrough in this area. By combining femtosecond angle-resolved spectroscopic imaging with interferometry, they directly observed the transfer of laser coherence to resonantly excited exciton polaritons within hundreds of femtoseconds at room temperature. They further uncovered the physical mechanism by which non-resonant polaritons lose coherence under high pump power due to a decoherence process mediated by the exciton reservoir. These findings have been published under the title "Femtosecond coherence dynamics of exciton polaritons" in National Science Review. Haoyuan Jia, a PhD candidate at East China Normal University, is the first author, with co-corresponding authors including Prof. Jian Wu and Prof. Hui Li (East China Normal University), Dr. Junhui Cao (Moscow Institute of Physics and Technology), and Prof. Tim Byrnes (NYU Shanghai).

An international team of researchers have developed a novel hybrid detection system HALIMA at the Institute of Modern Physics to facilitate the measurement of the sub-nanosecond lifetimes of neutron-rich nuclei produced via fission. This system is composed of eight BGO-shielded HPGe detectors and 20 fast LaBr₃(Ce) detectors, each shielded with CsI(Tl), offering high-resolution γ-ray energy and timing capabilities. To enhance event selectivity, two specialized ancillary detector arrays were incorporated: a solar cell detector array for detecting fission fragments (FFs) and a fast plastic scintillator array for β-particle detection. These additions enable advanced coincidence techniques, such as FFs/β-GeLaBr₃(Ce)-LaBr₃(Ce), significantly improving the spectral quality and peak-to-background, thereby allowing precise lifetime measurements. A commissioning experiment using a ²⁵²Cf source was conducted to validate the performance of the HALIMA setup. By applying combined gating to FFs and fast plastic scintillators, the lifetimes of three excited nuclear states in ¹³⁴Te, ¹³⁸Ba, and ¹³²Te were measured, covering a range from a few picoseconds to several hundred nanoseconds.The results were in good agreement with the literature values, demonstrating the capability and precision of the HALIMA setup. Furthermore, several excited states with previously unmeasured lifetimes produced by ²⁵²Cf fission were identified for the first time, thereby opening new avenues for nuclear structure studies of neutron-rich nuclei.

With climate change posing an unprecedented global challenge, the demand for environmentally friendly solvents in green chemical processes and carbon dioxide capture has surged. Ionic liquids (ILs) have emerged as promising "designer solvents" due to their negligible volatility, broad liquid temperature range, and exceptional thermal stability. However, the immense chemical space of ILs—with theoretically up to 10¹⁸ possible cation-anion combinations—has created a critical bottleneck in efficient screening and design. Traditional experimental methods are costly and time-consuming, while theoretical calculations like molecular dynamics and quantum chemistry remain computationally prohibitive for large-scale screening. This urgent need for accelerated discovery has set the stage for a transformative technological leap.