A simple interferometer was used to monitor the seismic noise effect on the equivalence principle test using the free-fall interferometric method.The experimental result showed that this effect was belowλ/100,whereλ...A simple interferometer was used to monitor the seismic noise effect on the equivalence principle test using the free-fall interferometric method.The experimental result showed that this effect was belowλ/100,whereλis the wavelength of the laser beam,and the uncertainty of the differential gravity acceleration of the individual free-fall result due to this effect was about 0.6μGal.展开更多
A double-potential-well model is proposed to describe the core-shell thickness-dependent photoluminescence peaks and energy relaxations in semiconductor quantum dots (QDs). The surface effect plays an important role i...A double-potential-well model is proposed to describe the core-shell thickness-dependent photoluminescence peaks and energy relaxations in semiconductor quantum dots (QDs). The surface effect plays an important role in the formation of new states-polaronic states around the surface of QDs. The polaronic states formed emit light due to the strong interaction between the core state (confined state) and the surface state with an enhanced participation of the size effect.展开更多
We study a new kind of equivalence principle for rotating bodies and propose a test of the equivalence principle by comparing free-fall gravitational accelerations of two gyroscopes or a rotating and a non-rotating ex...We study a new kind of equivalence principle for rotating bodies and propose a test of the equivalence principle by comparing free-fall gravitational accelerations of two gyroscopes or a rotating and a non-rotating extended bodies.展开更多
Large two-photon absorption cross section of a novel compound trans-1,3,5-tri-(4-N,N-dimethylaminobenzylstyryl)-acetylacetone is measured to beσ_(2)=8.4×10^(-20)cm^(4)/GW orσ'_(2)=1.594×10^(-47)cm^(4)/...Large two-photon absorption cross section of a novel compound trans-1,3,5-tri-(4-N,N-dimethylaminobenzylstyryl)-acetylacetone is measured to beσ_(2)=8.4×10^(-20)cm^(4)/GW orσ'_(2)=1.594×10^(-47)cm^(4)/(photon.s)by using a 1064 nm Nd:YAG laser with 35 ps pulse width based on the intensity-dependent transmissivity measurement.The frequency upconversion fluorescence is observed by two-photon laser pumping.This material is an ideal candidate for optical limiting and upconversion fluorescence.展开更多
A fast melting release method for the free-fall equivalence principle test using laser interferometry is discussed.The primary experiment result shows that the uncertainty of the differential release time could be con...A fast melting release method for the free-fall equivalence principle test using laser interferometry is discussed.The primary experiment result shows that the uncertainty of the differential release time could be controlled at the level of 1ms by this release system,which satisfies the requirement of the expected experimental precision.展开更多
The upconversion luminescence of several YbEr co-doped Zr-Ba-La-Al-Na(ZBLAN)glass samples(Er(0.5)Yb(3):ZBLAN,Er(0.5)Yb(1):ZBLAN and Er(0.5):ZBLAN)has been studied.A new kind of upconversion cooperative radiation fluor...The upconversion luminescence of several YbEr co-doped Zr-Ba-La-Al-Na(ZBLAN)glass samples(Er(0.5)Yb(3):ZBLAN,Er(0.5)Yb(1):ZBLAN and Er(0.5):ZBLAN)has been studied.A new kind of upconversion cooperative radiation fluorescence,which comes from coupled cluster states of two Yb^(3+)ions has been observed.This is significant in that it may lead to a new path to achieve blue upconversion luminescence,which has promising upconversion applications.展开更多
Fick's first law is modified with an additional term df(x)/dx to describe the segregation phenomenon,f(x)is a local,analytical function related to the depth profile at equilibrium.It thus can be determined experim...Fick's first law is modified with an additional term df(x)/dx to describe the segregation phenomenon,f(x)is a local,analytical function related to the depth profile at equilibrium.It thus can be determined experimentally by depth profiling technique.Segregation starting in an initially homogeneous solid is described by an inhomogeneous diffusion equation on the half-infinite domain.Segregation with and without formation of overlayer suggests different boundary conditions.The solution for the Ansatz f(x)=as exp(-x/d_(s))is in perfect agreement with experimental results on sulphur segregation to the surface of titanium.Independent from the detailed kinetics,activation energy can be inferred from the surface concentration evolution under different temperatures.For sulphur segregation in titanium,E_(act)=718 meV/atom.展开更多
The generation of UV radiation at 285.4nm by four-wave mixing in magnesium vapor is reported.A dye-laser radiation is focused into magnesium vapor and tuned to the resonance wavelength of the two-photon transition 3s^...The generation of UV radiation at 285.4nm by four-wave mixing in magnesium vapor is reported.A dye-laser radiation is focused into magnesium vapor and tuned to the resonance wavelength of the two-photon transition 3s^(2)1S0-3s^(4s) 1S0.The dependence of the signal intensity at 285.4nm on Mg vapor density and incident laser power has been measured and the spectral behaviour has been studied.展开更多
基金Supported by the Ministry of Science and Technology of China under Grant No.95-Yu-34the National Natural Science Foundation of China under Grant No.19835040。
文摘A simple interferometer was used to monitor the seismic noise effect on the equivalence principle test using the free-fall interferometric method.The experimental result showed that this effect was belowλ/100,whereλis the wavelength of the laser beam,and the uncertainty of the differential gravity acceleration of the individual free-fall result due to this effect was about 0.6μGal.
基金Supported by the Bairen Project of the Chinese Academy of Sciences.
文摘A double-potential-well model is proposed to describe the core-shell thickness-dependent photoluminescence peaks and energy relaxations in semiconductor quantum dots (QDs). The surface effect plays an important role in the formation of new states-polaronic states around the surface of QDs. The polaronic states formed emit light due to the strong interaction between the core state (confined state) and the surface state with an enhanced participation of the size effect.
基金Supported partially by the Ministry of Science and Technology of China under Grant No.95-Yu-34the National Natural Science Foundation of China under Grant No.19835040.
文摘We study a new kind of equivalence principle for rotating bodies and propose a test of the equivalence principle by comparing free-fall gravitational accelerations of two gyroscopes or a rotating and a non-rotating extended bodies.
基金Supported by the National Natural Science Foundation of China under Grant Nos.29832030 and 20072039the Foundation of Laboratory of Optical Physics at the Institute of Physics,Chinese Academy of Sciences.
文摘Large two-photon absorption cross section of a novel compound trans-1,3,5-tri-(4-N,N-dimethylaminobenzylstyryl)-acetylacetone is measured to beσ_(2)=8.4×10^(-20)cm^(4)/GW orσ'_(2)=1.594×10^(-47)cm^(4)/(photon.s)by using a 1064 nm Nd:YAG laser with 35 ps pulse width based on the intensity-dependent transmissivity measurement.The frequency upconversion fluorescence is observed by two-photon laser pumping.This material is an ideal candidate for optical limiting and upconversion fluorescence.
基金Supported by the Ministry of Science and Technology of China under Grant No.95-Yu-34the National Natural Science Foundation of China under Grant No.19835040.
文摘A fast melting release method for the free-fall equivalence principle test using laser interferometry is discussed.The primary experiment result shows that the uncertainty of the differential release time could be controlled at the level of 1ms by this release system,which satisfies the requirement of the expected experimental precision.
基金Supported by the National Natural Science Foundation of China under Grant No.19874033the Open Research Fund of the Institute of Physics and the Institute of Semiconductor Physics,Chinese Academy of Sciencesthe State Kay Program for Basic Research in China(G1998061311).
文摘The upconversion luminescence of several YbEr co-doped Zr-Ba-La-Al-Na(ZBLAN)glass samples(Er(0.5)Yb(3):ZBLAN,Er(0.5)Yb(1):ZBLAN and Er(0.5):ZBLAN)has been studied.A new kind of upconversion cooperative radiation fluorescence,which comes from coupled cluster states of two Yb^(3+)ions has been observed.This is significant in that it may lead to a new path to achieve blue upconversion luminescence,which has promising upconversion applications.
基金Supported by the Volkswagen Foundation,Hannover,Germany.
文摘Fick's first law is modified with an additional term df(x)/dx to describe the segregation phenomenon,f(x)is a local,analytical function related to the depth profile at equilibrium.It thus can be determined experimentally by depth profiling technique.Segregation starting in an initially homogeneous solid is described by an inhomogeneous diffusion equation on the half-infinite domain.Segregation with and without formation of overlayer suggests different boundary conditions.The solution for the Ansatz f(x)=as exp(-x/d_(s))is in perfect agreement with experimental results on sulphur segregation to the surface of titanium.Independent from the detailed kinetics,activation energy can be inferred from the surface concentration evolution under different temperatures.For sulphur segregation in titanium,E_(act)=718 meV/atom.
文摘The generation of UV radiation at 285.4nm by four-wave mixing in magnesium vapor is reported.A dye-laser radiation is focused into magnesium vapor and tuned to the resonance wavelength of the two-photon transition 3s^(2)1S0-3s^(4s) 1S0.The dependence of the signal intensity at 285.4nm on Mg vapor density and incident laser power has been measured and the spectral behaviour has been studied.
