The optical waveguiding lithium niobate(LiNbO_(3))films have been prepared on(001)-oriented SiO_(2) substrates by pulsed lager deposition technique.The x-ray diffraction and scanning electron microscopy were used to c...The optical waveguiding lithium niobate(LiNbO_(3))films have been prepared on(001)-oriented SiO_(2) substrates by pulsed lager deposition technique.The x-ray diffraction and scanning electron microscopy were used to characterize the as-grown films,and revealed that highly(012)-textured LiNbO_(3) films with smooth surface were achieved.The optical waveguiding properties of these films were demonstrated by m-line measurements of transverse-magnetic and transverse-electric multimodes.展开更多
Raman scattering experiments from acoustic phonons in Fibonacci metallic Nb-Cu superlattices were performed.The main features of the experimental results show that the Raman spectrum is dominated by triplet peaks whic...Raman scattering experiments from acoustic phonons in Fibonacci metallic Nb-Cu superlattices were performed.The main features of the experimental results show that the Raman spectrum is dominated by triplet peaks which originate from the density of states of longitudinal-acoustic(LA)phonons in the subbands of phonon dispersion.The expected rich structure of gaps in the phonon spectrum has been labeled by strongest diffraction wave vector factor nτP.展开更多
By employing a gettered annealing technique,we studied the relationship between the resistivity p(x,T)(20℃≤T≤300℃)and oxygen content»n the high-Tc superconductor YBa_(2)Cu_(3)O_(7-x).ρ(x,T)is approximately l...By employing a gettered annealing technique,we studied the relationship between the resistivity p(x,T)(20℃≤T≤300℃)and oxygen content»n the high-Tc superconductor YBa_(2)Cu_(3)O_(7-x).ρ(x,T)is approximately linear for 0.0≤x≤0.6,and both the slope dp/dT and the residual resistivity increase continuously with decreasing oxygen content.A qualitative analysis is given.展开更多
Conductive ferroelectric domain walls have attracted increasing research interest in the field of nanoelectronics,and the fabrication technique for such domain walls is vital.In this study,we investigated in detail th...Conductive ferroelectric domain walls have attracted increasing research interest in the field of nanoelectronics,and the fabrication technique for such domain walls is vital.In this study,we investigated in detail the fabrication of conductive domain walls in x-cut congruent thin-film lithium niobate(TFLN)using an electrical-field poling technique.The ferroelectric domain structures can be controlled through the applied electrical field and applied pulse numbers,and the domain inversion process is related to the conduction characteristics of the domain walls.The domain structures in TFLN are revealed using confocal second-harmonic microscopy and piezoresponse force microscopy.The results provide further directions for the development and application of conductive domain walls in TFLN.展开更多
A periodically-poled LiNbO3(PPLN) crystal features space-dependent second-order nonlinear coefficients, which is one of the most important materials to effectively control nonlinear optical interactions through quasi-...A periodically-poled LiNbO3(PPLN) crystal features space-dependent second-order nonlinear coefficients, which is one of the most important materials to effectively control nonlinear optical interactions through quasi-phase matching(QPM). By using electric-field poling method, 1D and 2D PPLN crystals have been successfully fabricated for laser frequency conversion, quantum light sources, nonlinear beam shaping and nonlinear optical imaging. Recently, femtosecond laser engineering technique is utilized to prepare 3D domain structures inside LiNbO3 crystal, which provides a promising platform to control nonlinear interacting waves in 3D configuration. After 40 years of developments, PPLN crystals still have exciting prospects in fundamental researches and practical applications for integrated photonic chip, quantum information processing,and so on.展开更多
We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal wit...We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal with duty cycle near 50% was fabricated using electrical poling at room temperature and pumped by a Raman fiber amplifier.We tested two temperature control ovens,and a maximum conversion efficiency of about 14.3%,corresponding to 4 W of yellow light with 28 W of fundamental power,and bandwidth less than 0.18 GHz was achieved.展开更多
基金Supported by the National Natural Science Foundation of Chinathe Climbing Plan Project of China.
文摘The optical waveguiding lithium niobate(LiNbO_(3))films have been prepared on(001)-oriented SiO_(2) substrates by pulsed lager deposition technique.The x-ray diffraction and scanning electron microscopy were used to characterize the as-grown films,and revealed that highly(012)-textured LiNbO_(3) films with smooth surface were achieved.The optical waveguiding properties of these films were demonstrated by m-line measurements of transverse-magnetic and transverse-electric multimodes.
基金Project supported by the National Science Foundation of China.
文摘Raman scattering experiments from acoustic phonons in Fibonacci metallic Nb-Cu superlattices were performed.The main features of the experimental results show that the Raman spectrum is dominated by triplet peaks which originate from the density of states of longitudinal-acoustic(LA)phonons in the subbands of phonon dispersion.The expected rich structure of gaps in the phonon spectrum has been labeled by strongest diffraction wave vector factor nτP.
文摘By employing a gettered annealing technique,we studied the relationship between the resistivity p(x,T)(20℃≤T≤300℃)and oxygen content»n the high-Tc superconductor YBa_(2)Cu_(3)O_(7-x).ρ(x,T)is approximately linear for 0.0≤x≤0.6,and both the slope dp/dT and the residual resistivity increase continuously with decreasing oxygen content.A qualitative analysis is given.
文摘Conductive ferroelectric domain walls have attracted increasing research interest in the field of nanoelectronics,and the fabrication technique for such domain walls is vital.In this study,we investigated in detail the fabrication of conductive domain walls in x-cut congruent thin-film lithium niobate(TFLN)using an electrical-field poling technique.The ferroelectric domain structures can be controlled through the applied electrical field and applied pulse numbers,and the domain inversion process is related to the conduction characteristics of the domain walls.The domain structures in TFLN are revealed using confocal second-harmonic microscopy and piezoresponse force microscopy.The results provide further directions for the development and application of conductive domain walls in TFLN.
基金supported by the National Key R&D Program of China(Grant Nos. 2017YFA0303703 and 2016YFA0302500)the National Natural Science Foundation of China (Grant Nos. 91950206,11874213 and11674171)the Fundamental Research Funds for the Central Universities (Grant Nos. 14380105 and 1480605201)。
文摘A periodically-poled LiNbO3(PPLN) crystal features space-dependent second-order nonlinear coefficients, which is one of the most important materials to effectively control nonlinear optical interactions through quasi-phase matching(QPM). By using electric-field poling method, 1D and 2D PPLN crystals have been successfully fabricated for laser frequency conversion, quantum light sources, nonlinear beam shaping and nonlinear optical imaging. Recently, femtosecond laser engineering technique is utilized to prepare 3D domain structures inside LiNbO3 crystal, which provides a promising platform to control nonlinear interacting waves in 3D configuration. After 40 years of developments, PPLN crystals still have exciting prospects in fundamental researches and practical applications for integrated photonic chip, quantum information processing,and so on.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11004025,11174046,11104131)
文摘We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal with duty cycle near 50% was fabricated using electrical poling at room temperature and pumped by a Raman fiber amplifier.We tested two temperature control ovens,and a maximum conversion efficiency of about 14.3%,corresponding to 4 W of yellow light with 28 W of fundamental power,and bandwidth less than 0.18 GHz was achieved.
