A series of glasses with high Bi2O3 content of Bi2O3-B2O3-WO3 ternary system were chosen and prepared .Their densities and linear refractive indices increase with increasing WO3 content. The optical band gaps Eopt of ...A series of glasses with high Bi2O3 content of Bi2O3-B2O3-WO3 ternary system were chosen and prepared .Their densities and linear refractive indices increase with increasing WO3 content. The optical band gaps Eopt of glasses obtained from ultraviolet absorption edges decreases with increase of WO3 content. Z-scan technique was carried out to investigate the third-order nonlinear optical properties of the glasses. It is found that the nonlinear refraction γ increases with decreasing the optical band gap Eopt, since an increase of WO3 content can promote the non-bridging oxygen ion content, and the highest γ value of samples is 1.173×10-14 cm2/W. The results show that these glasses are potential materials in the application of third-order nonlinear optics field.展开更多
40 Li_(2)O–5WO_(3)–(55-x)B_(2)O_(3):xV_(2)O_(5)(mol%)for 0.0≤x≤0.8 glasses were prepared by melt-quenching.Electric polarization was described in terms of the dielectric constant("0)and loss(tanδ).Mixed cond...40 Li_(2)O–5WO_(3)–(55-x)B_(2)O_(3):xV_(2)O_(5)(mol%)for 0.0≤x≤0.8 glasses were prepared by melt-quenching.Electric polarization was described in terms of the dielectric constant("0)and loss(tanδ).Mixed conduction phenomenon was explained by redox pairs V^(4+)↔V^(5+)and W^(5+)↔W^(6+) at high temperatures.Electronic polarizability(αe)was determined over a range of frequencies(100 Hz–100 kHz)and temperatures(30–280℃).The change of boron coordination in the glass network was explained with the aid of temperature coefficient of polarizability(φ).Nonlinear susceptibility(χ^((3)))and optical band gap(E°)were studied as a function of concentration of V_(2)O_(5).The highest values ofαe andχ^((3))were obtained at x=0.6 mol%.These glasses may find potential practical applications in the fields of solid-state ionics and nonlinear optics.展开更多
The third-order optical nonlinearities, includ- ing third-order nonlinear susceptibility χ(3), nonlinear refrac- tive index (n2) and temporal response, were measured with forward DFWM using Nd:YAG mode-locked pulse l...The third-order optical nonlinearities, includ- ing third-order nonlinear susceptibility χ(3), nonlinear refrac- tive index (n2) and temporal response, were measured with forward DFWM using Nd:YAG mode-locked pulse laser. The results show that Eu2O3 doped 5ZnO-20Nb2O5-75TeO2 glasses have large n2 and ultra-fast temporal response. Ra- man spectra show that Eu2O3 dopant induces the changes in the local structure of glasses. The higher the dopant concen- tration, the larger the nonlinear refractive n2 and the faster the temporal response. The enhancement on the third-order optical nonlinearities can be attributed to the deformation of the electronic clouds in [TeO4] enhanced by Eu2O3 dopant.展开更多
Colloidal Au and poly(vinylpyrrolidone) (PVP) composite thin films are fabricated by spin-coating method. Linear optical absorption measurements of the Au/PVP composite films indicate an absorption peak around 530...Colloidal Au and poly(vinylpyrrolidone) (PVP) composite thin films are fabricated by spin-coating method. Linear optical absorption measurements of the Au/PVP composite films indicate an absorption peak around 530 nm due to the surface plasmon resonance of gold nanoparticles. Nonlinear optical properties are studied using standard Z-scan technique, and experimental results show large optical nonlinearities of the Au/PVP composite films. A large value of χ^(3)/α up to 0.56× 10-^10esu·cm is obtained, which is comparable to the best values reported in metal/oxlde composite films.展开更多
Ag nanoparticles embedded in soda-lime silicate glass were fabricated by ion-exchange and subsequently annealing method. Effects of annealing duration on the optical nonlinearity and ultrafast dynamics of Ag nanoparti...Ag nanoparticles embedded in soda-lime silicate glass were fabricated by ion-exchange and subsequently annealing method. Effects of annealing duration on the optical nonlinearity and ultrafast dynamics of Ag nanoparticles in glass were investigated by z-scan technique and pump-probe technique. The results indicate that the third-order optical nonlinearity increases with extending the annealing time, the fast decay process with lifetime of a few picoseconds is attributed to thermal equilibrium process of hot electrons and the energy transfer to lattices by interaction with phonons in the formed Ag nanoparticles, while the slow decay in more than one hundred picoseconds corresponds to the subsequent cooling process by a thermal diffusion from the Ag nanoparticle to the host matrix via the phonon-medium interaction. The fast decay process is accelerated with extending the annealing time.展开更多
The second-order nonlinear optical susceptibilities β, βμ, and third-order non-linear optical susceptibilities γ, 〈γ〉 of a series of the novel push-pull multi-ring electro-photo polymer intermediates have been ...The second-order nonlinear optical susceptibilities β, βμ, and third-order non-linear optical susceptibilities γ, 〈γ〉 of a series of the novel push-pull multi-ring electro-photo polymer intermediates have been calculated. The influences of molecular structure, donor, acceptor and the frequency of external field on β and γ, and the relationship between γ and the number of thiophene rings (i. e. conjugated chain length) have been studied using INDO/SCI methods combined with sum-overstate (SOS) formula. The calculated results show that γ is proportional to 2.69 power of the chain length of the conjugated molecular bonds when the length is not quite long.展开更多
基金Funded by the National Natural Science Foundation of China (No.60677015)the Science and Technology Department of Zhejiang Province (No.2007C21122)the Natural Science Foundation of Ningbo (No.2006A610020)
文摘A series of glasses with high Bi2O3 content of Bi2O3-B2O3-WO3 ternary system were chosen and prepared .Their densities and linear refractive indices increase with increasing WO3 content. The optical band gaps Eopt of glasses obtained from ultraviolet absorption edges decreases with increase of WO3 content. Z-scan technique was carried out to investigate the third-order nonlinear optical properties of the glasses. It is found that the nonlinear refraction γ increases with decreasing the optical band gap Eopt, since an increase of WO3 content can promote the non-bridging oxygen ion content, and the highest γ value of samples is 1.173×10-14 cm2/W. The results show that these glasses are potential materials in the application of third-order nonlinear optics field.
基金The authors wish to thank management of VNRVJIET for their support to accomplish this research work.And,the authors(Dr.L.Srinivasa Rao and Dr.P.Raghavendra Rao)would like to thank Jawaharlal Nehru Technological Uni-versity Hyderabad for awarding a research project(Proc.No.JNTUH/TEQIP-III/CRS/2019/Physics/06).
文摘40 Li_(2)O–5WO_(3)–(55-x)B_(2)O_(3):xV_(2)O_(5)(mol%)for 0.0≤x≤0.8 glasses were prepared by melt-quenching.Electric polarization was described in terms of the dielectric constant("0)and loss(tanδ).Mixed conduction phenomenon was explained by redox pairs V^(4+)↔V^(5+)and W^(5+)↔W^(6+) at high temperatures.Electronic polarizability(αe)was determined over a range of frequencies(100 Hz–100 kHz)and temperatures(30–280℃).The change of boron coordination in the glass network was explained with the aid of temperature coefficient of polarizability(φ).Nonlinear susceptibility(χ^((3)))and optical band gap(E°)were studied as a function of concentration of V_(2)O_(5).The highest values ofαe andχ^((3))were obtained at x=0.6 mol%.These glasses may find potential practical applications in the fields of solid-state ionics and nonlinear optics.
文摘The third-order optical nonlinearities, includ- ing third-order nonlinear susceptibility χ(3), nonlinear refrac- tive index (n2) and temporal response, were measured with forward DFWM using Nd:YAG mode-locked pulse laser. The results show that Eu2O3 doped 5ZnO-20Nb2O5-75TeO2 glasses have large n2 and ultra-fast temporal response. Ra- man spectra show that Eu2O3 dopant induces the changes in the local structure of glasses. The higher the dopant concen- tration, the larger the nonlinear refractive n2 and the faster the temporal response. The enhancement on the third-order optical nonlinearities can be attributed to the deformation of the electronic clouds in [TeO4] enhanced by Eu2O3 dopant.
文摘Colloidal Au and poly(vinylpyrrolidone) (PVP) composite thin films are fabricated by spin-coating method. Linear optical absorption measurements of the Au/PVP composite films indicate an absorption peak around 530 nm due to the surface plasmon resonance of gold nanoparticles. Nonlinear optical properties are studied using standard Z-scan technique, and experimental results show large optical nonlinearities of the Au/PVP composite films. A large value of χ^(3)/α up to 0.56× 10-^10esu·cm is obtained, which is comparable to the best values reported in metal/oxlde composite films.
基金Funded by the National Natural Science Foundation of China (No.50672069)Key Item for Basic Research of Shanghai (No.05JC14058)
文摘Ag nanoparticles embedded in soda-lime silicate glass were fabricated by ion-exchange and subsequently annealing method. Effects of annealing duration on the optical nonlinearity and ultrafast dynamics of Ag nanoparticles in glass were investigated by z-scan technique and pump-probe technique. The results indicate that the third-order optical nonlinearity increases with extending the annealing time, the fast decay process with lifetime of a few picoseconds is attributed to thermal equilibrium process of hot electrons and the energy transfer to lattices by interaction with phonons in the formed Ag nanoparticles, while the slow decay in more than one hundred picoseconds corresponds to the subsequent cooling process by a thermal diffusion from the Ag nanoparticle to the host matrix via the phonon-medium interaction. The fast decay process is accelerated with extending the annealing time.
基金Project supported by the National Natural Science Foundation of China (No. 29890210)
文摘The second-order nonlinear optical susceptibilities β, βμ, and third-order non-linear optical susceptibilities γ, 〈γ〉 of a series of the novel push-pull multi-ring electro-photo polymer intermediates have been calculated. The influences of molecular structure, donor, acceptor and the frequency of external field on β and γ, and the relationship between γ and the number of thiophene rings (i. e. conjugated chain length) have been studied using INDO/SCI methods combined with sum-overstate (SOS) formula. The calculated results show that γ is proportional to 2.69 power of the chain length of the conjugated molecular bonds when the length is not quite long.