Do you want to publish a course? Click here

Producing translationally cold, ground-state CO molecules

89   0   0.0 ( 0 )
 Added by Janneke Blokland
 Publication date 2011
  fields Physics
and research's language is English




Ask ChatGPT about the research

Carbon monoxide molecules in their electronic, vibrational, and rotational ground state are highly attractive for trapping experiments. The optical or ac electric traps that can be envisioned for these molecules will be very shallow, however, with depths in the sub-milliKelvin range. Here we outline that the required samples of translationally cold CO (X$^1Sigma^+$, $v$=0, $N$=0) molecules can be produced after Stark deceleration of a beam of laser-prepared metastable CO (a$^3Pi_1$) molecules followed by optical transfer of the metastable species to the ground state emph{via} perturbed levels in the A$^1Pi$ state. The optical transfer scheme is experimentally demonstrated and the radiative lifetimes and the electric dipole moments of the intermediate levels are determined.

rate research

Read More

We trap cold, ground-state, argon atoms in a deep optical dipole trap produced by a build-up cavity. The atoms, which are a general source for the sympathetic cooling of molecules, are loaded in the trap by quenching them from a cloud of laser-cooled metastable argon atoms. Although the ground state atoms cannot be directly probed, we detect them by observing the collisional loss of co-trapped metastable argon atoms using a new type of parametric loss spectroscopy. Using this technique we also determine the polarizability ratio between the ground and the metastable 4s[3/2]$_2$ state to be 40$pm6$ and find a polarisability of (7.3$pm$1.1) $times$10$^{-39}$ Cm$^2/$V for the metastable state. Finally, Penning and associative losses of metastable atoms, in the absence of light assisted collisions, are determined to be $(3.3pm 0.8) times 10^{-10}$ cm$^3$s$^{-1}$.
We here report on the realization of an electrodynamic trap, capable of trapping neutral atoms and molecules in both low-field and high-field seeking states. Confinement in three dimensions is achieved by switching between two electric field configurations that have a saddle-point at the center of the trap, i.e., by alternating a focusing and a defocusing force in each direction. AC trapping of 15ND3 molecules is experimentally demonstrated, and the stability of the trap is studied as a function of the switching frequency. A 1 mK sample of 15ND3 molecules in the high-field seeking component of the |J,K>=|1,1> level, the ground-state of para-ammonia, is trapped in a volume of about 1 mm^3.
We report on the direct conversion of laser-cooled 41K and 87Rb atoms into ultracold 41K87Rb molecules in the rovibrational ground state via photoassociation followed by stimulated Raman adiabatic passage. High-resolution spectroscopy based on the coherent transfer revealed the hyperfine structure of weakly bound molecules in an unexplored region. Our results show that a rovibrationally pure sample of ultracold ground-state molecules is achieved via the all-optical association of laser-cooled atoms, opening possibilities to coherently manipulate a wide variety of molecules.
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 report the creation of a sample of over 1000 ultracold $^{87}$RbCs molecules in the lowest rovibrational ground state, from an atomic mixture of $^{87}$Rb and Cs, by magnetoassociation on an interspecies Feshbach resonance followed by stimulated Raman adiabatic passage (STIRAP). We measure the binding energy of the RbCs molecule to be $h c times 3811.576(1)$ cm$^{-1}$ and the $|v=0, J=0>$ to $|v=0, J=2>$ splitting to be $h times 2940.09(6)$ MHz. Stark spectroscopy of the rovibrational ground state yields an electric dipole moment of 1.225(3)(8) D, where the values in parentheses are the statistical and systematic uncertainties, respectively. We demonstrate that a space-fixed dipole moment of 0.355(2)(4) D is accessible in RbCs, which is substantially higher than in previous work.
comments
Fetching comments Fetching comments
Sign in to be able to follow your search criteria
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا