An extensive analysis of biexciton luminescence in high-quality,large perovskite CsPbBr_(3) nanocrystals shows how the biexciton Auger decay rate deviates from the"universal"volume scaling as the exciton con...An extensive analysis of biexciton luminescence in high-quality,large perovskite CsPbBr_(3) nanocrystals shows how the biexciton Auger decay rate deviates from the"universal"volume scaling as the exciton confinement becomes weaker.展开更多
Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging systems.However,owing to their low average powers,only raster-based images can be taken,resulting in sl...Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging systems.However,owing to their low average powers,only raster-based images can be taken,resulting in slow acquisition.In this work,we show that by placing a photoconductive switch within a cavity,we are able to generate absolute average THz powers of 181μW with the frequency of the THz emission centered at 1.5 THz-specifications ideally adapted to applications such as non-destructive imaging.The cavity is based on a metal-insulator-metal structure that permits an en hancement of the average power by almost 1 order of magnitude compared to a standard structure,while conserving a broadband spectral response.We demonstrate proof-of-principle real-time imaging using this source,with the broadband spectrum permitting to eliminate strong diffraction artifacts.展开更多
We study N-cluster correlation functions in four-and five-dimensional(4D)and 5D)bond percolation by extensive Monte Carlo simulation.We reformulate the transfer Monte Carlo algorithm for percolation[Phys.Reu.E 72,0161...We study N-cluster correlation functions in four-and five-dimensional(4D)and 5D)bond percolation by extensive Monte Carlo simulation.We reformulate the transfer Monte Carlo algorithm for percolation[Phys.Reu.E 72,016126(2005)]using the disjoint-set data structure,and simulate a cylindrical geometry Ld^-1×∞,with the linear size up to L=512 for 4D and 128 for 5D.We determine with 1 high precision all possible N-cluster exponents,for N=2 and 3,and the universal amplitude for a logarithmic correlation function.From the symmetric correlator with N=2,we obtain the correlation-length critical exponent as 1/v=1.4610(12)for 4D and 1/v=1.737(2)for 5D,significantly improving over the existing results.Estimates for the other exponents and the universal logarithmic amplitude have not been reported before to our knowledge.Our work demonstrates the validity of logarithmic conformal field theory and adds to the growing knowledge for high-dimensional percolation.展开更多
文摘An extensive analysis of biexciton luminescence in high-quality,large perovskite CsPbBr_(3) nanocrystals shows how the biexciton Auger decay rate deviates from the"universal"volume scaling as the exciton confinement becomes weaker.
基金H2020 Future and Emerging Technologies(MIRBOSE 737017)French RENATECH network.
文摘Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging systems.However,owing to their low average powers,only raster-based images can be taken,resulting in slow acquisition.In this work,we show that by placing a photoconductive switch within a cavity,we are able to generate absolute average THz powers of 181μW with the frequency of the THz emission centered at 1.5 THz-specifications ideally adapted to applications such as non-destructive imaging.The cavity is based on a metal-insulator-metal structure that permits an en hancement of the average power by almost 1 order of magnitude compared to a standard structure,while conserving a broadband spectral response.We demonstrate proof-of-principle real-time imaging using this source,with the broadband spectrum permitting to eliminate strong diffraction artifacts.
基金We dedicate this work to Fred(Fa-Yueh)Wu who passed away on January 21,2020.Known internationally for his contributions in statistical mechanics and solid state physics,Wu was a professor at Northeastern University for 39 years until his retirement in 2006 as Matthews Distinguished University Professor of Physics.His seminal review article on the Potts model[7]has benefitted several generations of statistical physicists.His broad interests in influence on his research community were illustrated by the special issue[56]that one of us(J.L.J.)co-edited for his 80 years birthday.In 2004,Wu was a member of the doctoral dissertation committee of another of us(Y.D.),and subsequently gave him a lot of encouragement throughout his academic career.We are indebted to Romain Couvreur for valuable discussions.Y.D.acknowledges the support by the National Natural Science Foundation of China(Grant No.11625522)the Ministry of Science and Technology of China(Grant No.2016YFA0301604).J.L.J.acknowledges support of the European Research Council through the Advanced Grant NuQFT.Simulations were carried out at the Supercomputing Center of the University of Science and Technology of China.
文摘We study N-cluster correlation functions in four-and five-dimensional(4D)and 5D)bond percolation by extensive Monte Carlo simulation.We reformulate the transfer Monte Carlo algorithm for percolation[Phys.Reu.E 72,016126(2005)]using the disjoint-set data structure,and simulate a cylindrical geometry Ld^-1×∞,with the linear size up to L=512 for 4D and 128 for 5D.We determine with 1 high precision all possible N-cluster exponents,for N=2 and 3,and the universal amplitude for a logarithmic correlation function.From the symmetric correlator with N=2,we obtain the correlation-length critical exponent as 1/v=1.4610(12)for 4D and 1/v=1.737(2)for 5D,significantly improving over the existing results.Estimates for the other exponents and the universal logarithmic amplitude have not been reported before to our knowledge.Our work demonstrates the validity of logarithmic conformal field theory and adds to the growing knowledge for high-dimensional percolation.
