We investigate the many-body wave function of a quantum system with time-dependent effective mass, confined by a harmonic potential with time-dependent frequency, and perturbed by a time-dependent spatially homogeneou...We investigate the many-body wave function of a quantum system with time-dependent effective mass, confined by a harmonic potential with time-dependent frequency, and perturbed by a time-dependent spatially homogeneous electric field. It is found that the wave function is comprised of a phase factor times the solution to the unperturbed time-dependent Schr6dinger equation with the latter being translated by a time-dependent value that satisfies the classical driven equation of motion. The wave function reduces to that of the harmonic potential theorem wave function when both the effective mass and frequency are static. An example of application is also given.展开更多
To further improve sensor sensitivity,a strain and temperature sensor based on the harmonic Vernier effect with cascaded Sagnac interferometers(SIs)is proposed.Through a combination of simulation and experimentation,i...To further improve sensor sensitivity,a strain and temperature sensor based on the harmonic Vernier effect with cascaded Sagnac interferometers(SIs)is proposed.Through a combination of simulation and experimentation,it is shown that the basic Vernier effect can be realized when the lengths of the polarization-maintaining fiber(PMF)in two SIs are slightly different.Furthermore,the first-order harmonic Vernier effect can be achieved when the lengths of two PMFs are approximately integer multiples.This sensor,leveraging the harmonic Vernier effect,demonstrates higher sensitivity.Compared to a single SI,the strain sensitivity based on the basic Vernier effect is improved to 61.93 pm/µεwith a magnification factor of 7.6,and the temperature sensitivity is improved to 14.29 nm/℃with a magnification factor of 9.4.For the first-order harmonic Vernier effect,the strain sensitivity increases to 146.35 pm/µεwith a magnification factor of 18,and the temperature sensitivity increases to 24.92 nm/℃with a magnification factor of 16.5.Additionally,the sensor based on the harmonic Vernier effect exhibits good stability in strain and temperature measurement.Unlike the basic Vernier effect,the harmonic Vernier effect does not require strict control of the reference and sensing interferometer lengths,further increasing sensitivity.Due to its simple structure and low cost,the proposed sensor shows significant potential for applications in high-precision measurement engineering and medical treatment.展开更多
Increasing simultaneously both the cutoff energy and efficiency is a big challenge to all applications of high-order harmonic generation(HHG).For this purpose,the shaping of the waveform of driving pulse is an alterna...Increasing simultaneously both the cutoff energy and efficiency is a big challenge to all applications of high-order harmonic generation(HHG).For this purpose,the shaping of the waveform of driving pulse is an alternative approach.Here,we show that the harmonic cutoff can be extended by about two times without reducing harmonic yield after considering macroscopic propagation effects,by adopting a practical way to synthesize two-color fields with fixed energy.Our results,combined with the experimental techniques,show the great potential of HHG as a tabletop light source.展开更多
The real-time second harmonic generation was employed to investigate the[2＋2]photodimerization of styrylquinoline（SQ） derivatives in Langmuir-Blodgett（LB） monolayers deposited from aqueous subphases with differen...The real-time second harmonic generation was employed to investigate the[2＋2]photodimerization of styrylquinoline（SQ） derivatives in Langmuir-Blodgett（LB） monolayers deposited from aqueous subphases with different acidity.It was discovered that the photodimerization rate constant significantly decreased upon the addition of acid.The additional atomic force microscopy measurements revealed that surface morphologies were correlated to the photodimerization kinetics.These experimental results provide direct evidence for the topo-chemical mechanisms of[2＋2]photodimerization in LB films.The current study demonstrates that the intermolecular interactions and aggregation structures play important roles in the photochemical properties at surfaces.展开更多
A new nonlinear optical crystal of sodium terbium borate （Na2.67Tb2.11B3O9, Mr = 573.14） was synthesized by solid reaction method. The colorless transparent single crystals were grown from the high temperature solut...A new nonlinear optical crystal of sodium terbium borate （Na2.67Tb2.11B3O9, Mr = 573.14） was synthesized by solid reaction method. The colorless transparent single crystals were grown from the high temperature solution by employing NaBO2 as flux. The structure was deter- mined by single-crystal X-ray diffraction method. The compound crystallizes in the orthorhombic system, space group Amm2 with a = 5.0744（10）, b = 10.990（2）, c = 6.9078（14） A, V = 385.24（13） A3, Dc = 4.941 g/cm3, F（000） = 250, Z = 2, μ= 9.205 mm-1, the final R = 0.0253 and wR = 0.0610. Its three-dimensional network structure is constructed from isolated BO33-, Na（1）O8, Na（2）O6, Na（3）O6 and Tb（1）O9 polyhedra. Variable-temperature magnetic susceptibility measurements show the compound is paramagnetic （μj = 7.04 μb）. The intensity of the second harmonic generation of Na2.67Tb2.11B3O9 is 2.5 times that of KDP.展开更多
To improve the sensitivity measurement of temperature sensors,a fiber optic temperature sensor structure based on the harmonic Vernier effect with two parallel fiber Sagnac interferometers(FSIs)is designed,and theoret...To improve the sensitivity measurement of temperature sensors,a fiber optic temperature sensor structure based on the harmonic Vernier effect with two parallel fiber Sagnac interferometers(FSIs)is designed,and theoretical analysis and experimental testing are conducted.The FSI consisting of two polarization maintaining fibers(PMFs)with lengths of 13.62 m and 15.05 m respectively is used to achieve the basic Vernier effect.Then by changing the length of one PMF to approximately i times that of the others,the FSI composed of two PMFs of 7.1 m and 15.05 m is used to achieve the first-order harmonic Vernier effect.Afterward,temperature sensing tests are conducted to observe the wavelength drift during temperature changes and ultimately achieve high sensitivity.The experimental results show that the temperature sensitivity of the sensor based on the first-order harmonic Vernier effect is-28.89 nm/℃,which is 17.09 times that of a single FSI structure(-1.69 nm/℃)and 1.84 times that of the sensitivity generated by the structure based on the basic Vernier effect(-15.69 nm/℃).The experimental results are consistent with the theoretical analysis.The structure proposed in this paper achieves drift measurement of 0.1℃ variation based on 1 drift,making the fiber optic temperature sensor applicable to related fields that requir e high precision temperature.The proposed temperature sensor has the simple structure,low production cost,high sensitivity,and broad application prospects.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11275100the K.C.Wong Magna Foundation of Ningbo University
文摘We investigate the many-body wave function of a quantum system with time-dependent effective mass, confined by a harmonic potential with time-dependent frequency, and perturbed by a time-dependent spatially homogeneous electric field. It is found that the wave function is comprised of a phase factor times the solution to the unperturbed time-dependent Schr6dinger equation with the latter being translated by a time-dependent value that satisfies the classical driven equation of motion. The wave function reduces to that of the harmonic potential theorem wave function when both the effective mass and frequency are static. An example of application is also given.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFB3209500)Shenzhen Science and Technology Program,China(Grant No.JCYJ20220818095800001)+2 种基金China Postdoctoral Science Foundation(Grant No.2024T170579)National Natural Science Foundation of China(Grant No.62374111)Guangdong Basic and Applied Basic Research Foundation,China(Grant No.2024A1515010164).
文摘To further improve sensor sensitivity,a strain and temperature sensor based on the harmonic Vernier effect with cascaded Sagnac interferometers(SIs)is proposed.Through a combination of simulation and experimentation,it is shown that the basic Vernier effect can be realized when the lengths of the polarization-maintaining fiber(PMF)in two SIs are slightly different.Furthermore,the first-order harmonic Vernier effect can be achieved when the lengths of two PMFs are approximately integer multiples.This sensor,leveraging the harmonic Vernier effect,demonstrates higher sensitivity.Compared to a single SI,the strain sensitivity based on the basic Vernier effect is improved to 61.93 pm/µεwith a magnification factor of 7.6,and the temperature sensitivity is improved to 14.29 nm/℃with a magnification factor of 9.4.For the first-order harmonic Vernier effect,the strain sensitivity increases to 146.35 pm/µεwith a magnification factor of 18,and the temperature sensitivity increases to 24.92 nm/℃with a magnification factor of 16.5.Additionally,the sensor based on the harmonic Vernier effect exhibits good stability in strain and temperature measurement.Unlike the basic Vernier effect,the harmonic Vernier effect does not require strict control of the reference and sensing interferometer lengths,further increasing sensitivity.Due to its simple structure and low cost,the proposed sensor shows significant potential for applications in high-precision measurement engineering and medical treatment.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11264036,11164025,11364038the Specialize Research Fund for the Doctoral Program of Higher Education of China under Grant No.20116203120001the Basic Scientific Researc Foundation for Institution of Higher Learning of Gansu Province
文摘Increasing simultaneously both the cutoff energy and efficiency is a big challenge to all applications of high-order harmonic generation(HHG).For this purpose,the shaping of the waveform of driving pulse is an alternative approach.Here,we show that the harmonic cutoff can be extended by about two times without reducing harmonic yield after considering macroscopic propagation effects,by adopting a practical way to synthesize two-color fields with fixed energy.Our results,combined with the experimental techniques,show the great potential of HHG as a tabletop light source.
基金supported by the National Natural Science Foundation of China(Nos.21473217,21227802 and 21303216)the Chinese Ministry of Science and Technology(No.2013CB834504)
文摘The real-time second harmonic generation was employed to investigate the[2＋2]photodimerization of styrylquinoline（SQ） derivatives in Langmuir-Blodgett（LB） monolayers deposited from aqueous subphases with different acidity.It was discovered that the photodimerization rate constant significantly decreased upon the addition of acid.The additional atomic force microscopy measurements revealed that surface morphologies were correlated to the photodimerization kinetics.These experimental results provide direct evidence for the topo-chemical mechanisms of[2＋2]photodimerization in LB films.The current study demonstrates that the intermolecular interactions and aggregation structures play important roles in the photochemical properties at surfaces.
基金supported by the National Natural Science Foundation of China (91022025, 51072036)the Natural Science Foundation of Fujian Province (2010J01284)
文摘A new nonlinear optical crystal of sodium terbium borate （Na2.67Tb2.11B3O9, Mr = 573.14） was synthesized by solid reaction method. The colorless transparent single crystals were grown from the high temperature solution by employing NaBO2 as flux. The structure was deter- mined by single-crystal X-ray diffraction method. The compound crystallizes in the orthorhombic system, space group Amm2 with a = 5.0744（10）, b = 10.990（2）, c = 6.9078（14） A, V = 385.24（13） A3, Dc = 4.941 g/cm3, F（000） = 250, Z = 2, μ= 9.205 mm-1, the final R = 0.0253 and wR = 0.0610. Its three-dimensional network structure is constructed from isolated BO33-, Na（1）O8, Na（2）O6, Na（3）O6 and Tb（1）O9 polyhedra. Variable-temperature magnetic susceptibility measurements show the compound is paramagnetic （μj = 7.04 μb）. The intensity of the second harmonic generation of Na2.67Tb2.11B3O9 is 2.5 times that of KDP.
基金supported by the Primary Research and Development Plan of Zhejiang Province,China(Grant No.2023C03014)the Key Research and Development Program of Zhejiang Province,China(Grant No.2022C03037).
文摘To improve the sensitivity measurement of temperature sensors,a fiber optic temperature sensor structure based on the harmonic Vernier effect with two parallel fiber Sagnac interferometers(FSIs)is designed,and theoretical analysis and experimental testing are conducted.The FSI consisting of two polarization maintaining fibers(PMFs)with lengths of 13.62 m and 15.05 m respectively is used to achieve the basic Vernier effect.Then by changing the length of one PMF to approximately i times that of the others,the FSI composed of two PMFs of 7.1 m and 15.05 m is used to achieve the first-order harmonic Vernier effect.Afterward,temperature sensing tests are conducted to observe the wavelength drift during temperature changes and ultimately achieve high sensitivity.The experimental results show that the temperature sensitivity of the sensor based on the first-order harmonic Vernier effect is-28.89 nm/℃,which is 17.09 times that of a single FSI structure(-1.69 nm/℃)and 1.84 times that of the sensitivity generated by the structure based on the basic Vernier effect(-15.69 nm/℃).The experimental results are consistent with the theoretical analysis.The structure proposed in this paper achieves drift measurement of 0.1℃ variation based on 1 drift,making the fiber optic temperature sensor applicable to related fields that requir e high precision temperature.The proposed temperature sensor has the simple structure,low production cost,high sensitivity,and broad application prospects.
