A fold optical path is utilized to capture and launch atoms in the atomic fountain. This improved technique reduces the laser power needed by 60 percent, facilitates suppression of the laser power fluctuations, and le...A fold optical path is utilized to capture and launch atoms in the atomic fountain. This improved technique reduces the laser power needed by 60 percent, facilitates suppression of the laser power fluctuations, and leads to a more simple and stable system.展开更多
Ultracold plasma provides a possible route to approach the strongly-coupled regime under laboratory conditions. Normally, the lifetime of ultracold plasma is very limited due to plasma heating and expansion mechanisms...Ultracold plasma provides a possible route to approach the strongly-coupled regime under laboratory conditions. Normally, the lifetime of ultracold plasma is very limited due to plasma heating and expansion mechanisms. We present a new method to generate long lifetime ultracold plasmas consisting mainly of cations and anions. This plasma demonstrates a capability of traversing a DC barrier of up to 5 （or -3） V. The lifetime of this plasma is expected to be more than 250us. Finally, molecular dynamics （MD） simulation is used to explain how anions slow the expansion rate and prolong the lifetime of this plasma.展开更多
We demonstrated two experimental methods of producing and guiding pulsed atomic beams on chip. One is to trap atoms first in a U-type magneto-optical trap on the chip, then transfer them to the magnetic guide field an...We demonstrated two experimental methods of producing and guiding pulsed atomic beams on chip. One is to trap atoms first in a U-type magneto-optical trap on the chip, then transfer them to the magnetic guide field and push them simultaneously by a continuous force from the power imbalance of the magneto-optical trap laser beams hence the pulsed cold atom beams are produced and move along the magnetic guide to the destination. The other is to trap atoms directly by a H-type magneto-optical trap, then push them to make them move along the magnetic guide field, thus high rate cold atom beams can be produced and guided on the chip.展开更多
This paper introduces Bohmian mechanics （BM） into the intense laser-atom physics to study high-order harmonic generation. In BM, the trajectories of atomic electron in an intense laser field can be obtained with the...This paper introduces Bohmian mechanics （BM） into the intense laser-atom physics to study high-order harmonic generation. In BM, the trajectories of atomic electron in an intense laser field can be obtained with the Bohm--Newton equation. The power spectrum with the trajectory of an atomic electron is calculated, which is found to be irregular. Next, the power spectrum associated with an atom ensemble from BM is considered, where the power spectrum becomes regular and consistent with that from quantum mechanics. Finally, the reason of the generation of the irregular spectrum is discussed.展开更多
Using Schrodinger-Maxwell formalism, we propose and analyze a continuous-wave four-wave mixing (FWM) scheme for the generation of coherent light in a six-level atomic system based on electromag-netically dual induced ...Using Schrodinger-Maxwell formalism, we propose and analyze a continuous-wave four-wave mixing (FWM) scheme for the generation of coherent light in a six-level atomic system based on electromag-netically dual induced transparency. We derive the corresponding explicit analytical expressions for the generated mixing field. We find that the scheme greatly enhances FWM production efficiency and is also capable of inhibiting and delaying the onset of the detrimental three-photon destructive interference by choosing the proper decay rate in the second electromagnetically induced transparency (EIT) process. In addition, such an optical process also provides possibilities for producing short-wave-length coherent radiation at low pump intensities.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 10974215)the Science Foundation of State Key Laboratory of Precision Spectroscopy,East China Normal University
文摘A fold optical path is utilized to capture and launch atoms in the atomic fountain. This improved technique reduces the laser power needed by 60 percent, facilitates suppression of the laser power fluctuations, and leads to a more simple and stable system.
基金supported by National Natural Science Foundation of China(No.21043010)the Research Foundation of the Key Laboratory of Chemical Lasers of Dalian Institute of Chemical Physics(No.KLCL-2011-N4)
文摘Ultracold plasma provides a possible route to approach the strongly-coupled regime under laboratory conditions. Normally, the lifetime of ultracold plasma is very limited due to plasma heating and expansion mechanisms. We present a new method to generate long lifetime ultracold plasmas consisting mainly of cations and anions. This plasma demonstrates a capability of traversing a DC barrier of up to 5 （or -3） V. The lifetime of this plasma is expected to be more than 250us. Finally, molecular dynamics （MD） simulation is used to explain how anions slow the expansion rate and prolong the lifetime of this plasma.
基金supported by the National Basic Research Program of China (Grant Nos. 2005CB724505/1 and 2006CB921203)the National Natural Science Foundation of China (Grant No. 10774160)the Science Foundation of Wuhan National Laboratory for Optoelectronics (Grant No. P080001)
文摘We demonstrated two experimental methods of producing and guiding pulsed atomic beams on chip. One is to trap atoms first in a U-type magneto-optical trap on the chip, then transfer them to the magnetic guide field and push them simultaneously by a continuous force from the power imbalance of the magneto-optical trap laser beams hence the pulsed cold atom beams are produced and move along the magnetic guide to the destination. The other is to trap atoms directly by a H-type magneto-optical trap, then push them to make them move along the magnetic guide field, thus high rate cold atom beams can be produced and guided on the chip.
文摘This paper introduces Bohmian mechanics （BM） into the intense laser-atom physics to study high-order harmonic generation. In BM, the trajectories of atomic electron in an intense laser field can be obtained with the Bohm--Newton equation. The power spectrum with the trajectory of an atomic electron is calculated, which is found to be irregular. Next, the power spectrum associated with an atom ensemble from BM is considered, where the power spectrum becomes regular and consistent with that from quantum mechanics. Finally, the reason of the generation of the irregular spectrum is discussed.
基金This work was supported in part by the National Natural Science Foundation of China under Grant No. 90103026 and 10125419.
文摘Using Schrodinger-Maxwell formalism, we propose and analyze a continuous-wave four-wave mixing (FWM) scheme for the generation of coherent light in a six-level atomic system based on electromag-netically dual induced transparency. We derive the corresponding explicit analytical expressions for the generated mixing field. We find that the scheme greatly enhances FWM production efficiency and is also capable of inhibiting and delaying the onset of the detrimental three-photon destructive interference by choosing the proper decay rate in the second electromagnetically induced transparency (EIT) process. In addition, such an optical process also provides possibilities for producing short-wave-length coherent radiation at low pump intensities.
