Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping appro...Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping approach of a slave Raman laser within an optical phase-locked loop(OPLL),which finds practical application in an atomic gravimeter,where the OPLL frequently switches between near-resonance lasers and significantly detuned Raman lasers.The method merges the advantages of rapid and extensive frequency hopping with the OPLL’s inherent low phase noise,and exhibits a versatile range of applications in compact laser systems,promising advancements in portable instruments.展开更多
The systematical and scalable frameworks were provided for estimating the blocking probabilities under asynchronous traffic in optical burst switching(OBS) nodes with limited wavelength conversion capability(LWCC) . T...The systematical and scalable frameworks were provided for estimating the blocking probabilities under asynchronous traffic in optical burst switching(OBS) nodes with limited wavelength conversion capability(LWCC) . The relevant system architectures of limited range and limited number of wavelength converters(WCs) deployed by a share-per-fiber(SPF) mode were developed,and the novel theoretical analysis of node blocking probability was derived by combining the calculation of discouraged arrival rate in a birth-death process and two-dimensional Markov chain model of SPF. The simulation results on single node performance verify the accuracy and effectiveness of the analysis models. Under most scenarios,it is difficult to distinguish the plots generated by the analysis and simulation. As the conversion degree increases,the accuracy of the analysis model worsens slightly. However,the utmost error on burst loss probability is far less than one order of magnitude and hence,still allows for an accurate estimate. Some results are of actual significance to the construction of next-generation commercial OBS backbones.展开更多
Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in ea...Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic sub-states.Compared to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks.展开更多
We experimentally demonstrate a Faraday laser at Rb 1529 nm transition by using a performance-improved Rb electrodeless-discharge-lamp-based excited-state Faraday anomalous dispersion optical filter as the frequencyse...We experimentally demonstrate a Faraday laser at Rb 1529 nm transition by using a performance-improved Rb electrodeless-discharge-lamp-based excited-state Faraday anomalous dispersion optical filter as the frequencyselective element. Neither the electrical locking scheme nor the additional frequency-stabilized pump laser are used. The frequency of the external-cavity diode laser is stabilized to the Rb 1529 nm transition, and the Allan deviation of the Faraday laser is measured by converting the optical intensity into frequency. The Faraday laser can be used as a frequency standard in the telecom C band for further research on metrology, microwave photonics, and optical communication systems.展开更多
The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneo...The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneous transition probabilities with rate equations. At the same time, the population density of energy level is also obtained. The results provide the potential applications of electrodeless discharge lamp in atomic filter and optical frequency reference at higher excited states without a pumping laser.展开更多
In order to realize laser frequency stabilization,the global evolution of an analyzer angle on the electrodeless-discharge-vaporlamp-based excited-state Faraday anomalous dispersion optical filter(LESFADOF)with a sing...In order to realize laser frequency stabilization,the global evolution of an analyzer angle on the electrodeless-discharge-vaporlamp-based excited-state Faraday anomalous dispersion optical filter(LESFADOF)with a single transmission peak operating on the Rb1529 nm(5P3/2-4D5/2)is presented.We find that the transmission of the line center peak at 80°arrives at 14%in a 3 cm length lamp contained natural Rb mixed with 2 torr Xe buffer gas operating at 250°C with 176 MHz radio frequency.When it is used to realize laser frequency stabilization,the LESFADOF at near 80°is appropriate.Whether a single transmission peak or double transmission peaks depend on the rf voltage when two polarizers are crossed.展开更多
We demonstrate a narrowband optical filter which operates on the 52S1/2 to 52P3/2 transition at 780 nm in rubidium vapor based on optical-pumping-induced dichroism combined with Faraday anomalous dispersion effects. I...We demonstrate a narrowband optical filter which operates on the 52S1/2 to 52P3/2 transition at 780 nm in rubidium vapor based on optical-pumping-induced dichroism combined with Faraday anomalous dispersion effects. Its peak transmission is 18.4(2)% at the 52S1/2,F = 2 to 52P3/2,F′ = 1,3 crossover transition,whereas at the 52S1/2,F = 2 to 52P3/2,F′ = 2,3 crossover transition the transmission is 18.6(2)%. Both transitions have a bandwidth(full-width at half-maximum of peak transmission) as narrow as 24.5(8) MHz,which is remarkably improved compared with the narrowest bandwidth as we know. This technique can also be applied to other alkali atoms.展开更多
The intensities of fluorescence spectral lines of Ca atoms and Sr atoms in two different hollow cathode lamps(HCLs) are measured by element-balance-detection technology. In the wavelength range of 350–750 nm in the v...The intensities of fluorescence spectral lines of Ca atoms and Sr atoms in two different hollow cathode lamps(HCLs) are measured by element-balance-detection technology. In the wavelength range of 350–750 nm in the visible spectral region, using the individual strongest line(Ca 422.67 nm, Sr 460.73 nm) as the bench mark,the population ratios between the excited states of Ca atoms and Sr atoms are calculated by rate equations and the spontaneous transition probabilities. The HCLs with populations at excited states can be used to realize the frequency stabilization reference of the laser frequency standard.展开更多
The sub-Doppler absorption laser spectroscopy at 728 nm transition from the 5D5/2 state to the 6 F state of cesium with linewidth near 10 MHz is first experimentally performed with indirect pumping from the ground sta...The sub-Doppler absorption laser spectroscopy at 728 nm transition from the 5D5/2 state to the 6 F state of cesium with linewidth near 10 MHz is first experimentally performed with indirect pumping from the ground state 6S_(1/2)to the state 7P_(3/2)by a 455.5 nm diode laser.Using a 455.5 nm diode laser as an indirect pump laser,several excited states will be populated due to spontaneous decay from the 7P state.We first implement the sub-Doppler absorption laser spectroscopy at 728 nm from the 5D_(5/2)state to the 6F state when Cs atoms within thermal glass cell decay to the 5D_(5/2) state.Due to velocity transfer effect,the hyperfine structure of 5D_(5/2)shows a mixed and complicated pattern but very clear structure when the 455.5 nm pumping laser is counter-propagating(or co-propagating)with the 728 nm probing laser.展开更多
Nonlinear spectroscopy has become a useful tool in laser cooling,frequency stabilization and so on.We use the 455.5 nm light beam output of an external cavity diode laser to perform the saturation spectroscopy signal ...Nonlinear spectroscopy has become a useful tool in laser cooling,frequency stabilization and so on.We use the 455.5 nm light beam output of an external cavity diode laser to perform the saturation spectroscopy signal and polarization spectroscopy signal on the 6S_(1/2)→7P3/2 transition in cesium.The measured linewidth of the F4→4,5 transition is as narrow as 1.40 MHz and that of the F3→2,3 transition is 1.67 MHz.Both of them are very close to the natural linewidth of about 1.2 MHz.Our result is the narrowest measured linewidth of Cs 455 nm saturation spectroscopy signal to our knowledge.展开更多
Population ratios between excited states are measured to build the excited state Faraday anomalous dispersion optical filter(ESFADOF).We calculate these values between the excited states according to the spontaneous t...Population ratios between excited states are measured to build the excited state Faraday anomalous dispersion optical filter(ESFADOF).We calculate these values between the excited states according to the spontaneous transition probabilities using rate equations and the measured intensities of fluorescence spectral lines of He atoms in an electrodeless discharge lamp in the visible spectral region from 350 to 730 nm.The electrodeless discharge lamp with populations in excited states can be used to realize the frequency stabilization reference of the laser frequency standard.This lamp can also build ESFADOFs for submarine communication application in the blue-green wavelength to simplify the system without the use of a pump laser.展开更多
We present a 657-nm external cavity diode laser (ECDL) system,where the output frequency is stabilized by a narrow-band high transmission interference filter.This novel diode laser system emits laser with an instantan...We present a 657-nm external cavity diode laser (ECDL) system,where the output frequency is stabilized by a narrow-band high transmission interference filter.This novel diode laser system emits laser with an instantaneous linewidth of 7 kHz and a broadened linewidth of 432 kHz.展开更多
So far, the only Ca magneto-optic atomic filters reported are based on a heated Ca cell, and the transmission spectrum obtained is double-peaked with 3 GHz effective passband limited by Doppler broadening. A magneto-o...So far, the only Ca magneto-optic atomic filters reported are based on a heated Ca cell, and the transmission spectrum obtained is double-peaked with 3 GHz effective passband limited by Doppler broadening. A magneto-optic atomic filter with single-peaked transmission spectrum of sub-Doppler bandwidth based on the thermal Ca atomic beam is firstly experimentally demonstrated. The fast Ca dipole transition(1S0–1P1) at 422.7 nm, which matches a strong solar Fraunhofer line, was utilized. A folded ninebeam traveling wave configuration is employed, and the maximum transmission efficiency is measured to be 7.3 %.A sub-Doppler transmission bandwidth of 590 MHz, much narrower than the 2.2 GHz Doppler width in the heated atomic cell, is obtained for the first time.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 10874009,11074011 and 91436210the International Science&Technology Cooperation Program of China under Grant No 2010DFR10900
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2021YFA0718300 and 2021YFA1400900)the National Natural Science Foundation of China(Grant Nos.11920101004,11934002,and 92365208)+1 种基金Science and Technology Major Project of Shanxi(Grant No.202101030201022)Space Application System of China Manned Space Program.
文摘Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping approach of a slave Raman laser within an optical phase-locked loop(OPLL),which finds practical application in an atomic gravimeter,where the OPLL frequently switches between near-resonance lasers and significantly detuned Raman lasers.The method merges the advantages of rapid and extensive frequency hopping with the OPLL’s inherent low phase noise,and exhibits a versatile range of applications in compact laser systems,promising advancements in portable instruments.
基金Supported by the National Basic Research Program of China under Grant No 2005CB724500, the National Natural Science Foundation of China under No 10874009, and Open Research Found of State Key Laboratory of Precision Spectroscopy （East China Normal University）.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10874009,11074011 and 91436210the International Science and Technology Cooperation Program of China under Grant No 2010DFR10900
基金Project(60632010) supported by the National Natural Science Foundation of China
文摘The systematical and scalable frameworks were provided for estimating the blocking probabilities under asynchronous traffic in optical burst switching(OBS) nodes with limited wavelength conversion capability(LWCC) . The relevant system architectures of limited range and limited number of wavelength converters(WCs) deployed by a share-per-fiber(SPF) mode were developed,and the novel theoretical analysis of node blocking probability was derived by combining the calculation of discouraged arrival rate in a birth-death process and two-dimensional Markov chain model of SPF. The simulation results on single node performance verify the accuracy and effectiveness of the analysis models. Under most scenarios,it is difficult to distinguish the plots generated by the analysis and simulation. As the conversion degree increases,the accuracy of the analysis model worsens slightly. However,the utmost error on burst loss probability is far less than one order of magnitude and hence,still allows for an accurate estimate. Some results are of actual significance to the construction of next-generation commercial OBS backbones.
基金Supported by the National Key Research and Development Program of China under Grant No 2016YFA0301501the National Natural Science Foundation of China under Grant Nos 61727819 and 91736208
文摘Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic sub-states.Compared to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10874009 and 11074011, and the International Science and Technology Cooperation Program of China under Grant No 2010DFR10900.
基金＊Supported by National Natural Science Foundation of China under Grant Nos 10874009, 11074011 and 91436210, and the International Science and Technology Cooperation Program of China under Grant No 2010DFR10900.
基金supported by the National Natural Science Foundation of China under Grant No.91436210
文摘We experimentally demonstrate a Faraday laser at Rb 1529 nm transition by using a performance-improved Rb electrodeless-discharge-lamp-based excited-state Faraday anomalous dispersion optical filter as the frequencyselective element. Neither the electrical locking scheme nor the additional frequency-stabilized pump laser are used. The frequency of the external-cavity diode laser is stabilized to the Rb 1529 nm transition, and the Allan deviation of the Faraday laser is measured by converting the optical intensity into frequency. The Faraday laser can be used as a frequency standard in the telecom C band for further research on metrology, microwave photonics, and optical communication systems.
基金supported by the National Natural Science Foundation of China (10874009 and 11074011)
文摘The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneous transition probabilities with rate equations. At the same time, the population density of energy level is also obtained. The results provide the potential applications of electrodeless discharge lamp in atomic filter and optical frequency reference at higher excited states without a pumping laser.
基金supported by the National Natural Science Foundation of China(10874009 and 11074011)
文摘In order to realize laser frequency stabilization,the global evolution of an analyzer angle on the electrodeless-discharge-vaporlamp-based excited-state Faraday anomalous dispersion optical filter(LESFADOF)with a single transmission peak operating on the Rb1529 nm(5P3/2-4D5/2)is presented.We find that the transmission of the line center peak at 80°arrives at 14%in a 3 cm length lamp contained natural Rb mixed with 2 torr Xe buffer gas operating at 250°C with 176 MHz radio frequency.When it is used to realize laser frequency stabilization,the LESFADOF at near 80°is appropriate.Whether a single transmission peak or double transmission peaks depend on the rf voltage when two polarizers are crossed.
基金supported by the National Natural Science Foundation of China(Nos.10874009 and 11074011)the National 863 Program of China
文摘We demonstrate a narrowband optical filter which operates on the 52S1/2 to 52P3/2 transition at 780 nm in rubidium vapor based on optical-pumping-induced dichroism combined with Faraday anomalous dispersion effects. Its peak transmission is 18.4(2)% at the 52S1/2,F = 2 to 52P3/2,F′ = 1,3 crossover transition,whereas at the 52S1/2,F = 2 to 52P3/2,F′ = 2,3 crossover transition the transmission is 18.6(2)%. Both transitions have a bandwidth(full-width at half-maximum of peak transmission) as narrow as 24.5(8) MHz,which is remarkably improved compared with the narrowest bandwidth as we know. This technique can also be applied to other alkali atoms.
基金supported by the National Natural Science Foundation of China(No.91436210)
文摘The intensities of fluorescence spectral lines of Ca atoms and Sr atoms in two different hollow cathode lamps(HCLs) are measured by element-balance-detection technology. In the wavelength range of 350–750 nm in the visible spectral region, using the individual strongest line(Ca 422.67 nm, Sr 460.73 nm) as the bench mark,the population ratios between the excited states of Ca atoms and Sr atoms are calculated by rate equations and the spontaneous transition probabilities. The HCLs with populations at excited states can be used to realize the frequency stabilization reference of the laser frequency standard.
基金Supported by the National Natural Science Foundation of China under Grant No 91436210
文摘The sub-Doppler absorption laser spectroscopy at 728 nm transition from the 5D5/2 state to the 6 F state of cesium with linewidth near 10 MHz is first experimentally performed with indirect pumping from the ground state 6S_(1/2)to the state 7P_(3/2)by a 455.5 nm diode laser.Using a 455.5 nm diode laser as an indirect pump laser,several excited states will be populated due to spontaneous decay from the 7P state.We first implement the sub-Doppler absorption laser spectroscopy at 728 nm from the 5D_(5/2)state to the 6F state when Cs atoms within thermal glass cell decay to the 5D_(5/2) state.Due to velocity transfer effect,the hyperfine structure of 5D_(5/2)shows a mixed and complicated pattern but very clear structure when the 455.5 nm pumping laser is counter-propagating(or co-propagating)with the 728 nm probing laser.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10874009 and 11074011.
文摘Nonlinear spectroscopy has become a useful tool in laser cooling,frequency stabilization and so on.We use the 455.5 nm light beam output of an external cavity diode laser to perform the saturation spectroscopy signal and polarization spectroscopy signal on the 6S_(1/2)→7P3/2 transition in cesium.The measured linewidth of the F4→4,5 transition is as narrow as 1.40 MHz and that of the F3→2,3 transition is 1.67 MHz.Both of them are very close to the natural linewidth of about 1.2 MHz.Our result is the narrowest measured linewidth of Cs 455 nm saturation spectroscopy signal to our knowledge.
基金supported by the National Natural Science Foundation of China under Grant Nos.10874009 and 11074011
文摘Population ratios between excited states are measured to build the excited state Faraday anomalous dispersion optical filter(ESFADOF).We calculate these values between the excited states according to the spontaneous transition probabilities using rate equations and the measured intensities of fluorescence spectral lines of He atoms in an electrodeless discharge lamp in the visible spectral region from 350 to 730 nm.The electrodeless discharge lamp with populations in excited states can be used to realize the frequency stabilization reference of the laser frequency standard.This lamp can also build ESFADOFs for submarine communication application in the blue-green wavelength to simplify the system without the use of a pump laser.
基金supported by the Ministry of Science and Technology of China (No. 2005CB724500)the National Natural Science Foundation of China (No. 10874009)
文摘We present a 657-nm external cavity diode laser (ECDL) system,where the output frequency is stabilized by a narrow-band high transmission interference filter.This novel diode laser system emits laser with an instantaneous linewidth of 7 kHz and a broadened linewidth of 432 kHz.
基金supported by the National Natural Science Foundation of China(10874009 and 11074011)
文摘So far, the only Ca magneto-optic atomic filters reported are based on a heated Ca cell, and the transmission spectrum obtained is double-peaked with 3 GHz effective passband limited by Doppler broadening. A magneto-optic atomic filter with single-peaked transmission spectrum of sub-Doppler bandwidth based on the thermal Ca atomic beam is firstly experimentally demonstrated. The fast Ca dipole transition(1S0–1P1) at 422.7 nm, which matches a strong solar Fraunhofer line, was utilized. A folded ninebeam traveling wave configuration is employed, and the maximum transmission efficiency is measured to be 7.3 %.A sub-Doppler transmission bandwidth of 590 MHz, much narrower than the 2.2 GHz Doppler width in the heated atomic cell, is obtained for the first time.
