The influence of an ionizing laser on the pump-probe spectra of^(87)Rb over the transition 5^(2)S_(1/2),F=2→5^(2)P_(3/2),F'=3 is experimentally studied in an operating magneto-optical trap.These spectral features...The influence of an ionizing laser on the pump-probe spectra of^(87)Rb over the transition 5^(2)S_(1/2),F=2→5^(2)P_(3/2),F'=3 is experimentally studied in an operating magneto-optical trap.These spectral features,including gain peak,a dispersion-like structure and absorption peak,become weak as the intensity of the ionizing laser increases.Moreover,the profiles of the absorption peak and gain peak vary as the ionizing laser intensity changes.Such results indicate that there is more than one component in the two features and that each component has different dependences on the number of^(87)Rb atoms.展开更多
We report the measurement of the absolute photoionization cross section for the 5P_(3/2 )state of ^(87) Rb at wavelength of 473 nm,which results in the photoelectron energies of 33 meV above the ionization threshold,u...We report the measurement of the absolute photoionization cross section for the 5P_(3/2 )state of ^(87) Rb at wavelength of 473 nm,which results in the photoelectron energies of 33 meV above the ionization threshold,using cold atoms confined in a vapor-loaded magneto-optical trap.The 87Rb 5P_(3/2 )photoionization cross section at 473nm is determined to be σ_(PI) =10.5 ± 2.2 Mb.Considering the spatial distribution of the trapped atoms,the average intensity I_(PI) of the ionization laser seen by an atom in the MOT instead of ionizing laser intensity I_(PI) is used in our calculations for the photoionization cross sections.The excited state fraction is also accurately estimated using the latest experimental result.展开更多
The autoionization distribution of the triply excited double Rydberg states(TEDRS)5d5/2NLnl(N≤22;n≤50;L,l<4)of La has been investigated by using five-laser resonance excitation in combination with a method of seq...The autoionization distribution of the triply excited double Rydberg states(TEDRS)5d5/2NLnl(N≤22;n≤50;L,l<4)of La has been investigated by using five-laser resonance excitation in combination with a method of sequential ionization by a pulsed electric field and a constant electric field.The experimental results exhibit that the La atoms in TEDRS predominantly single-autoionize to the ionic Rydberg states located in a few Rydberg manifolds.Furthermore,a difference of autoionization mechanisms between TEDRS above and those below the double ionization threshold is found.展开更多
The probe transmission spectra around the atomic transition 52S1/2,F = 2 → 52P3/2,F = 2 of 87Rb are measured in a magneto-optical trap by adding a coupling field around the atomic transition 52S1/2, F = 2 → 52 P3/2,...The probe transmission spectra around the atomic transition 52S1/2,F = 2 → 52P3/2,F = 2 of 87Rb are measured in a magneto-optical trap by adding a coupling field around the atomic transition 52S1/2, F = 2 → 52 P3/2, F1 = 2. The inversionless amplification is observed in the spectrum over the atomic transition 5 2 S1/2, F = 2 → 52pa/2, Fr = 2. The tripod eleetromagnetically induced transparency is proposed to account for the ampli- fication feature, in which population distributions among these related atomic levels play an important role.展开更多
基金the National Natural Science Foundation of China under Grant No 11074299Tsinghua University Initative Scientific Research Program under Grant No 20101081779.
文摘The influence of an ionizing laser on the pump-probe spectra of^(87)Rb over the transition 5^(2)S_(1/2),F=2→5^(2)P_(3/2),F'=3 is experimentally studied in an operating magneto-optical trap.These spectral features,including gain peak,a dispersion-like structure and absorption peak,become weak as the intensity of the ionizing laser increases.Moreover,the profiles of the absorption peak and gain peak vary as the ionizing laser intensity changes.Such results indicate that there is more than one component in the two features and that each component has different dependences on the number of^(87)Rb atoms.
基金Supported by the National Natural Science Foundation of China under Grant No 11074299Tsinghua University Initative Scientific Research Program under Grant No 20101081779.
文摘We report the measurement of the absolute photoionization cross section for the 5P_(3/2 )state of ^(87) Rb at wavelength of 473 nm,which results in the photoelectron energies of 33 meV above the ionization threshold,using cold atoms confined in a vapor-loaded magneto-optical trap.The 87Rb 5P_(3/2 )photoionization cross section at 473nm is determined to be σ_(PI) =10.5 ± 2.2 Mb.Considering the spatial distribution of the trapped atoms,the average intensity I_(PI) of the ionization laser seen by an atom in the MOT instead of ionizing laser intensity I_(PI) is used in our calculations for the photoionization cross sections.The excited state fraction is also accurately estimated using the latest experimental result.
基金Supported by the National Natural Science Foundation of China under Grant No.19734030,Ministry of Science and Technology,P.R.Chinaand China Postdoctoral Science Foundation.
文摘The autoionization distribution of the triply excited double Rydberg states(TEDRS)5d5/2NLnl(N≤22;n≤50;L,l<4)of La has been investigated by using five-laser resonance excitation in combination with a method of sequential ionization by a pulsed electric field and a constant electric field.The experimental results exhibit that the La atoms in TEDRS predominantly single-autoionize to the ionic Rydberg states located in a few Rydberg manifolds.Furthermore,a difference of autoionization mechanisms between TEDRS above and those below the double ionization threshold is found.
基金Supported by the National Natural Science Foundation of China under Grant No 11074299, and the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics.
文摘The probe transmission spectra around the atomic transition 52S1/2,F = 2 → 52P3/2,F = 2 of 87Rb are measured in a magneto-optical trap by adding a coupling field around the atomic transition 52S1/2, F = 2 → 52 P3/2, F1 = 2. The inversionless amplification is observed in the spectrum over the atomic transition 5 2 S1/2, F = 2 → 52pa/2, Fr = 2. The tripod eleetromagnetically induced transparency is proposed to account for the ampli- fication feature, in which population distributions among these related atomic levels play an important role.
