Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userFormation of ultracold RbCs molecules by photoassociation
137
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The formation of ultracold metastable RbCs molecules is observed in a double species magneto-optical trap through photoassociation below the ^85Rb(5S_1/2)+^133Cs(6P_3/2) dissociation limit followed by spontaneous emission. The molecules are detected by resonance enhanced two-photon ionization. Using accurate quantum chemistry calculations of the potential energy curves and transition dipole moment, we interpret the observed photoassociation process as occurring at short internuclear distance, in contrast with most previous cold atom photoassociation studies. The vibrational levels excited by photoassociation belong to the 5th 0^+ or the 4th 0^- electronic states correlated to the Rb(5P_1/2,3/2)+Cs(6S_1/2) dissociation limit. The computed vibrational distribution of the produced molecules shows that they are stabilized in deeply bound vibrational states of the lowest triplet state. We also predict that a noticeable fraction of molecules is produced in the lowest level of the electronic ground state.
rate research
Read More
Ultracold metastable RbCs molecules are observed in a double species MOT through photoassociation near the Rb(5S$_{1/2}$)+Cs(6P$_{3/2}$) dissociation limit followed by radiative stabilization. The molecules are formed in their lowest triplet electronic state and are detected by resonant enhanced two-photon ionization through the previously unobserved $(3)^{3}Pi leftarrow a^{3}Sigma^{+}$ band. The large rotational structure of the observed photoassociation lines is assigned to the lowest vibrational levels of the $0^+,0^-$ excited states correlated to the Rb(5P$_{1/2}$)+Cs(6S$_{1/2}$) dissociation limit. This demonstrates the possibility to induce direct photoassociation in heteronuclear alkali-metal molecules at short internuclear distance, as pointed out in [J. Deiglmayr textit{et al.}, Phys. Rev. Lett. textbf{101}, 13304 (2008)].
We demonstrate the direct formation of vibronic ground state RbCs molecules by photoassociation of ultracold atoms followed by radiative stabilization. The photoassociation proceeds through deeply-bound levels of the (2)^{3}Pi_{0^{+}} state. From analysis of the relevant free-to-bound and bound-to-bound Franck-Condon factors, we have predicted and experimentally verified a set of photoassociation resonances that lead to efficient creation of molecules in the v=0 vibrational level of the X^{1}Sigma^{+} electronic ground state. We also compare the observed and calculated laser intensity required to saturate the photoassociation rate. We discuss the prospects for using short-range photoassociation to create and accumulate samples of ultracold polar molecules in their rovibronic ground state.
We recently reported the formation of ultracold LiCs molecules in the rovibrational ground state X1Sigma+,v=0,J=0 [J. Deiglmayr et al., PRL 101, 133004 (2008)]. Here we discuss details of the experimental setup and present a thorough analysis of the photoassociation step including the photoassociation line shape. We predict the distribution of produced ground state molecules using accurate potential nergy curves combined with an ab-initio dipole transition moment and compare this prediction with experimental ionization spectra. Additionally we improve the value of the dissociation energy for the X1Sigma+ state by high resolution spectroscopy of the vibrational ground state.
We report the production of ultracold heteronuclear Cs$^*$Yb molecules through one-photon photoassociation applied to an ultracold atomic mixture of Cs and Yb confined in an optical dipole trap. We use trap-loss spectroscopy to detect molecular states below the Cs($^{2}P_{1/2}$) + Yb($^{1}S_{0}$) asymptote. For $^{133}$Cs$^{174}$Yb, we observe 13 rovibrational states with binding energies up to $sim$500 GHz. For each rovibrational state we observe two resonances associated with the Cs hyperfine structure and show that the hyperfine splitting in the diatomic molecule decreases for more deeply bound states. In addition, we produce ultracold fermionic $^{133}$Cs$^{173}$Yb and bosonic $^{133}$Cs$^{172}$Yb and $^{133}$Cs$^{170}$Yb molecules. From mass scaling, we determine the number of bound states supported by the 2(1/2) excited-state potential to be 154 or 155.
We report on the observation of blue-detuned photoassociation in Rb2, in which vibrational levels are energetically above the corresponding excited atomic asymptote. 85Rb atoms in a MOT were photoassociated at short internuclear distances to levels of the (1)3Pi g state at a rate of approximately 5x10^4 molecules/s. We have observed most of the predicted vibrational levels for all four spin-orbit components 0g+, 0g-, 1g, and 2g, including levels of the 0g+ outer well. These molecules decay to the metastable a3Sigma u+ state, some preferentially to the v=0 level, as we have observed for photoassociation to the v=8 level of the 1g component.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
