Frequencies of frequency standards are shifted by the local static gravity red shifts and also modulated by the tidal relativistic red shifts. We compute the tidal relativistic red shifts using a time-domain method an...Frequencies of frequency standards are shifted by the local static gravity red shifts and also modulated by the tidal relativistic red shifts. We compute the tidal relativistic red shifts using a time-domain method and present the numerical results for the National Institute of Metrology （NIM） in Beijing, Laboratoire National de Metrologie et Essais-Systeme de References Temps-Espaee （LNE-SYRTE） in Paris and Physikalisch-Teehnische Bundesanstalt （PTB） in Braunschweig. The differences of the tidal relativistic red shift approach as large as 1.1 × 10^-16 when frequency standards at NIM are compared with those at SYRTE and PTB. Moreover, the tidal relativistic red shifts of frequency standards in space stations are also computed.展开更多
In this work we present a study of a new method to prove the equation of the gravitational red shift of spec-tral lines. That’s according to the generalized special relativity theory. The equation of the gravitationa...In this work we present a study of a new method to prove the equation of the gravitational red shift of spec-tral lines. That’s according to the generalized special relativity theory. The equation of the gravitational red shift of spectral lines has been studied in many different works, using different methods depending on the Newtonian mechanics, and other theories. Although attention was drawn to the fact that the well-known ex-pression of the gravitational Red-Shift of spectral lines may be derived with no recourse to the general rela-tivity theory! In this study a unique derivation has been done using the Generalized Special Relativity (GSR) and the same result obtained.展开更多
A theoretical study on the red-shift of laser-induced electro-absorption is presented. It is found that laser-induced red-shift scales with the cube root of the pump laser intensity in the optical tunneling regime and...A theoretical study on the red-shift of laser-induced electro-absorption is presented. It is found that laser-induced red-shift scales with the cube root of the pump laser intensity in the optical tunneling regime and has an obvious deviation from this scale in the multi-photon regime. Our results show that in the optical tunneling regime, the laser-induced red shift has the same law as that in the direct current （DC） approximation. Though the scales are the same in the optical tunneling regime, the physical pictures in the two cases are quite different. The electro-absorption in the DC case is a tunneling-assisted transition process, while the laser-induced electro-absorption is a mixed multi-photon process.展开更多
Electrochromic phosphorescent materials have recently attracted much attention,however,achieving the efficient electrophosphorochromism in pure organic materials is highly challenging and has not been reported yet.Her...Electrochromic phosphorescent materials have recently attracted much attention,however,achieving the efficient electrophosphorochromism in pure organic materials is highly challenging and has not been reported yet.Herein,a kind of pure organic host-vip system(BA@Cz PA)is constructed by one-pot in-situ melt blending of(9-phenyl-9H-carbazol-2-yl)boronic acid(Cz PA)and boric acid(BA).Because of the efficient intersystem crossing promoted by covalent,hydrogen bonding,and confinement effect,the proposed BA@Cz PA exhibit the superior room temperature phosphorescence(RTP)efficiency,including an ultralong lifetime of up to 4.23 s and a high phosphorescent quantum yield of 10.9%.Importantly,the BA@Cz PA have a unique electrophosphorochromism property,and their electrically-induced RTP emission can gradually red-shift from 440 nm to 548 nm as the current density increases,which is attributed to the transformation of host matrices of BA@Cz PA from metaboric acid to B2O3under the electrical stimuli.This finding provides us not only with a new idea to develop pure organic electrophosphorochromism materials with high RTP efficiency,but also with a powerful strategy to fabricate correlation color temperature tunable white light emitting diodes.展开更多
A series of novel luminescent materials, SrZnO2:M (M=Eu3+, or Eu3+ + Li+) have been synthesized by high-temperature solid-state reaction. The structure and luminescence properties of SrZnO2:Eu3+ phosphor were studied ...A series of novel luminescent materials, SrZnO2:M (M=Eu3+, or Eu3+ + Li+) have been synthesized by high-temperature solid-state reaction. The structure and luminescence properties of SrZnO2:Eu3+ phosphor were studied through XRD, photoluminescence and Raman spectroscopy. The excitation spectra show a broad intense band and a number of small peaks corresponding to the inner 4f-shell excitations of Eu3+ (the strongest one is at 395 nm for 7F0-5L6). After SrZnO2:Eu3+ phosphor was co-doped with Li+ ions, its charge transfer band extended to longer wavelengths. This resulted in increase of luminescent quantum efficiency of the sample. SrZnO2:Eu3+,Li+ phosphor can be efficiently excited by longer UV. From the fluorescence spectrum of SrZnO2:Eu3+ phosphor, apart from transition emissions of 5D0 → 7FJ (J=0~4), the transition emissions from 5D1 → 7FJ (J=0~2) have been observed. For the SrZnO2:Eu3+ phosphor, under excitation of UV, the dominant emission is at about 612 nm, due to the 5D0 → 7F2 hypersensitive transition. The incorporation of Li+ ions greatly enhanced the luminescence intensity and made emission peak from 5D0 → 7F2 transition red-shifted.展开更多
基金Supported by the National Key R&D Program of China under Grant No 2016YFF0200200
文摘Frequencies of frequency standards are shifted by the local static gravity red shifts and also modulated by the tidal relativistic red shifts. We compute the tidal relativistic red shifts using a time-domain method and present the numerical results for the National Institute of Metrology （NIM） in Beijing, Laboratoire National de Metrologie et Essais-Systeme de References Temps-Espaee （LNE-SYRTE） in Paris and Physikalisch-Teehnische Bundesanstalt （PTB） in Braunschweig. The differences of the tidal relativistic red shift approach as large as 1.1 × 10^-16 when frequency standards at NIM are compared with those at SYRTE and PTB. Moreover, the tidal relativistic red shifts of frequency standards in space stations are also computed.
文摘In this work we present a study of a new method to prove the equation of the gravitational red shift of spec-tral lines. That’s according to the generalized special relativity theory. The equation of the gravitational red shift of spectral lines has been studied in many different works, using different methods depending on the Newtonian mechanics, and other theories. Although attention was drawn to the fact that the well-known ex-pression of the gravitational Red-Shift of spectral lines may be derived with no recourse to the general rela-tivity theory! In this study a unique derivation has been done using the Generalized Special Relativity (GSR) and the same result obtained.
基金Project supported by the Fundamental Research Funds for the Central Universities,China (Grant No.A735496)the National Natural Science Foundation of China (Grant No.61178018)the Ph.D. Funding Support Program of the Education Ministry of China (Grant No.20110185110007)
文摘A theoretical study on the red-shift of laser-induced electro-absorption is presented. It is found that laser-induced red-shift scales with the cube root of the pump laser intensity in the optical tunneling regime and has an obvious deviation from this scale in the multi-photon regime. Our results show that in the optical tunneling regime, the laser-induced red shift has the same law as that in the direct current （DC） approximation. Though the scales are the same in the optical tunneling regime, the physical pictures in the two cases are quite different. The electro-absorption in the DC case is a tunneling-assisted transition process, while the laser-induced electro-absorption is a mixed multi-photon process.
基金the financial support from the National Natural Science Foundation of China(No.22176058)Science and Technology Commission of Shanghai Municipality(Nos.24DX1400200,22ZR1416800,and 23ZR1416100)+1 种基金the Program of Introducing Talents of Discipline to Universities(No.B16017)the Fundamental Research Funds for the Central Universities(No.222201717003)。
文摘Electrochromic phosphorescent materials have recently attracted much attention,however,achieving the efficient electrophosphorochromism in pure organic materials is highly challenging and has not been reported yet.Herein,a kind of pure organic host-vip system(BA@Cz PA)is constructed by one-pot in-situ melt blending of(9-phenyl-9H-carbazol-2-yl)boronic acid(Cz PA)and boric acid(BA).Because of the efficient intersystem crossing promoted by covalent,hydrogen bonding,and confinement effect,the proposed BA@Cz PA exhibit the superior room temperature phosphorescence(RTP)efficiency,including an ultralong lifetime of up to 4.23 s and a high phosphorescent quantum yield of 10.9%.Importantly,the BA@Cz PA have a unique electrophosphorochromism property,and their electrically-induced RTP emission can gradually red-shift from 440 nm to 548 nm as the current density increases,which is attributed to the transformation of host matrices of BA@Cz PA from metaboric acid to B2O3under the electrical stimuli.This finding provides us not only with a new idea to develop pure organic electrophosphorochromism materials with high RTP efficiency,but also with a powerful strategy to fabricate correlation color temperature tunable white light emitting diodes.
文摘A series of novel luminescent materials, SrZnO2:M (M=Eu3+, or Eu3+ + Li+) have been synthesized by high-temperature solid-state reaction. The structure and luminescence properties of SrZnO2:Eu3+ phosphor were studied through XRD, photoluminescence and Raman spectroscopy. The excitation spectra show a broad intense band and a number of small peaks corresponding to the inner 4f-shell excitations of Eu3+ (the strongest one is at 395 nm for 7F0-5L6). After SrZnO2:Eu3+ phosphor was co-doped with Li+ ions, its charge transfer band extended to longer wavelengths. This resulted in increase of luminescent quantum efficiency of the sample. SrZnO2:Eu3+,Li+ phosphor can be efficiently excited by longer UV. From the fluorescence spectrum of SrZnO2:Eu3+ phosphor, apart from transition emissions of 5D0 → 7FJ (J=0~4), the transition emissions from 5D1 → 7FJ (J=0~2) have been observed. For the SrZnO2:Eu3+ phosphor, under excitation of UV, the dominant emission is at about 612 nm, due to the 5D0 → 7F2 hypersensitive transition. The incorporation of Li+ ions greatly enhanced the luminescence intensity and made emission peak from 5D0 → 7F2 transition red-shifted.
