Theoretical simulation of the photoassociation process for NaCs

Abstract

We investigate the two-step association process of NaCs using the time-dependent wave packet method. Ground state atoms can be photoassociated to the low vibrational levels of the ground state for an NaCs molecule by the two-step association. The time-dependent Schrödinger equation of the association process is solved within a three-state model and the wave packet is propagated with the "split operator-Fourier transform" scheme and the rotating-wave approximation (RWA). The vibrational population distribution of the ground state can be obtained by projecting the wave packet to every vibrational level of the ground state. The results not only show that for NaCs achievement of photoassociation production is accompanied by the photodissociation of the higher vibrational molecules, but also show that the vibrational distribution in lower vibrational levels of the ground state changes with the laser parameters.

Two-color laser modulation of magnetic Feshbach resonances

“…In the past decade, the control of quantum degenerate gases of ultracold atoms is widely studied by exploiting collisional resonances. [1][2][3][4] Many properties of ultracold gases depend on the s-wave scatting length. [5][6][7] Magnetic-fieldinduced Feshbach resonance (MFR) is an effective tool and has been applied widely to the research of alkali atomic gases to control the interaction between atoms.…”

Time-dependent approach to the double-channel dissociation of the NaCs molecule induced by pulsed lasers

“…In the investigation of light-molecule interaction, the dissociation of molecules has always been a very important topic, due to its significance in understanding both the nature of the potential energy curve (PEC) and the mechanism of the bond breaking process. [1] What is more, the progress of the photo-dissociation technique has made many new phenomena, such as multi-channel dissociation, [2] coherent control of dissociation, [3,4] photoassociation reaction, [5][6][7] etc observed and investigated. Among them, an interesting phenomenon is the double-channel dissociation.…”

“…In 2007, Aymar and Dulieu [19] reported first their calculated transition dipole moments, which laid a foundation for the study of the dissociation dynamics for the NaCs molecule. In the investigation of the two-step photoassociation of some cold molecules, [7,[20][21][22] it was found that the photo-dissociation is also a crucial process. The intensive theoretical and experimental researches on alkali-metal-atom molecules [7,23] showed that because of the features of their PECs, they have great possibilities to be dissociated through the double channels when being in the electronic ground state and exposed to laser fields.…”

“…In the investigation of the two-step photoassociation of some cold molecules, [7,[20][21][22] it was found that the photo-dissociation is also a crucial process. The intensive theoretical and experimental researches on alkali-metal-atom molecules [7,23] showed that because of the features of their PECs, they have great possibilities to be dissociated through the double channels when being in the electronic ground state and exposed to laser fields. So in the study of the external field effect on photo-dissociation dynamics, one often chooses the alkali-metal-atom molecules as a study object.…”

“…In addition, the TDWP method is especially suitable for the study of the real-time dynamics. It has given excellent results in the investigation of photo-ionization, [27] photodissociation, [28][29][30] photoassociation, [7] etc.…”