Tin halide perovskites recently have attracted extensive research attention due to their similar electronic and band structures but non-toxicity compared with their lead analogues. In this work, we prepare high-qualit...Tin halide perovskites recently have attracted extensive research attention due to their similar electronic and band structures but non-toxicity compared with their lead analogues. In this work, we prepare high-quality CsSnX_(3)(X=Br,I) microplates with lateral sizes of around 1–4 μm by chemical vapor deposition and investigate their low-temperature photoluminescence(PL) properties. A remarkable splitting of PL peaks of the CsSnBr_(3)microplate is observed at low temperatures. Besides the possible structural phase transition at below 70 K, the multi-peak fittings using Gauss functions and the power-dependent saturation phenomenon suggest that the PL could also be influenced by the conversion from the emission of bound excitons into free excitons. With the increase of temperature, the peak position shows a blueshift tendency for CsSnI_(3), which is governed by thermal expansion. However, the peak position of the CsSnBr3microplate exhibits a transition from redshift to blueshift at ~160 K. The full width at half maximum of CsSnX_(3)broadens with increasing temperature, and the fitting results imply that longitudinal optical phonons dominate the electron–phonon coupling and the coupling strength is much more robust in CsSnBr3than in CsSnI_(3). The PL intensity of CsSnX_(3)microplates is suppressed due to the enhanced non-radiative relaxation and exciton dissociation competing with radiative recombination. According to the Arrhenius law, the exciton binding energy of CsSnBr_(3)is ~38.4 meV, slightly smaller than that of CsSnI_(3).展开更多
Recently,the coexistence of topology and superconductivity has garnered considerable attention.Specifically,the dimensionality of these materials is crucial for the realization of topological quantum computation.Howev...Recently,the coexistence of topology and superconductivity has garnered considerable attention.Specifically,the dimensionality of these materials is crucial for the realization of topological quantum computation.However,the naturally grown materials,especially with one-dimensional feature that exhibits the coexistence of topology and superconductivity,still face challenges in terms of experimental realization and scalability,which hinders the fundamental research development and the potential to revolutionize quantum computing.Here,we report the first experimental synthesis of quasi-one-dimensional InNbS_(2)nanoribbons that exhibit the coexistence of topological order and superconductivity via a chemical vapor transport method.Especially,the inplane upper critical field of InNbS_(2)nanoribbons exceeds the Pauli paramagnetic limit by more than 2.2 times,which can be attributed to the enhanced spin-orbit coupling and the weakened interlayer interaction between the NbS_(2)layers induced by the insertion of In atoms,making InNbS_(2)exhibit spin-momentum locking similar to that of monolayer NbS_(2).Moreover,for the first time,we report the superconducting diode effect in a quasi-one-dimensional superconductor system without any inherent geometric imperfections.The measured maximum efficiency is manifested as 14%,observed atμ0H≈±60 mT,and we propose that the superconducting diode effect can potentially be attributed to the presence of the nontrivial topological band.Our work provides a platform for studying exotic phenomena in condensed matter physics and potential applications in quantum computing and quantum information processing.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11974279, 12074311, 12004310, and 12261141662)。
文摘Tin halide perovskites recently have attracted extensive research attention due to their similar electronic and band structures but non-toxicity compared with their lead analogues. In this work, we prepare high-quality CsSnX_(3)(X=Br,I) microplates with lateral sizes of around 1–4 μm by chemical vapor deposition and investigate their low-temperature photoluminescence(PL) properties. A remarkable splitting of PL peaks of the CsSnBr_(3)microplate is observed at low temperatures. Besides the possible structural phase transition at below 70 K, the multi-peak fittings using Gauss functions and the power-dependent saturation phenomenon suggest that the PL could also be influenced by the conversion from the emission of bound excitons into free excitons. With the increase of temperature, the peak position shows a blueshift tendency for CsSnI_(3), which is governed by thermal expansion. However, the peak position of the CsSnBr3microplate exhibits a transition from redshift to blueshift at ~160 K. The full width at half maximum of CsSnX_(3)broadens with increasing temperature, and the fitting results imply that longitudinal optical phonons dominate the electron–phonon coupling and the coupling strength is much more robust in CsSnBr3than in CsSnI_(3). The PL intensity of CsSnX_(3)microplates is suppressed due to the enhanced non-radiative relaxation and exciton dissociation competing with radiative recombination. According to the Arrhenius law, the exciton binding energy of CsSnBr_(3)is ~38.4 meV, slightly smaller than that of CsSnI_(3).
基金supported by Innovation Program for Quantum Science and Technology(No.2021ZD0302800)the National Natural Science Foundation of China(Nos.52373309 and 12374177)+1 种基金University of Macao Start-up research grant(No.SRG2023-00057-IAPME)National Synchrotron Radiation Laboratory(No.KY2060000177).
文摘Recently,the coexistence of topology and superconductivity has garnered considerable attention.Specifically,the dimensionality of these materials is crucial for the realization of topological quantum computation.However,the naturally grown materials,especially with one-dimensional feature that exhibits the coexistence of topology and superconductivity,still face challenges in terms of experimental realization and scalability,which hinders the fundamental research development and the potential to revolutionize quantum computing.Here,we report the first experimental synthesis of quasi-one-dimensional InNbS_(2)nanoribbons that exhibit the coexistence of topological order and superconductivity via a chemical vapor transport method.Especially,the inplane upper critical field of InNbS_(2)nanoribbons exceeds the Pauli paramagnetic limit by more than 2.2 times,which can be attributed to the enhanced spin-orbit coupling and the weakened interlayer interaction between the NbS_(2)layers induced by the insertion of In atoms,making InNbS_(2)exhibit spin-momentum locking similar to that of monolayer NbS_(2).Moreover,for the first time,we report the superconducting diode effect in a quasi-one-dimensional superconductor system without any inherent geometric imperfections.The measured maximum efficiency is manifested as 14%,observed atμ0H≈±60 mT,and we propose that the superconducting diode effect can potentially be attributed to the presence of the nontrivial topological band.Our work provides a platform for studying exotic phenomena in condensed matter physics and potential applications in quantum computing and quantum information processing.
