Cold and ultracold chemistry

The chemical and physical process involving charged and neutral particles with internal degrees of freedom

Atom-ion quantum hybrid systems

The development of hybrid trap technologies for simultaneous cooling and trapping of atoms and ions has brought about the possibility of studying chemical reactions between charged and neutral particles with significant control over the internal states of the collisional partners. This hybrid technology is appropriate to study ion-neutral collisional processes down to temperatures of a few mK. Only recently the field has evolved towards the study of molecular ion-neutral collisions.

In our group, we study vibrational and rotational relaxation of molecular ions in the presence of a buffer gas or ultracold atomic gas. As a few-body oriented group, we also study ion-atom-atom three-body recombination, which turns out to be the dominant reactive channel of an ion is immersed in a high-density ultracold gas. In most of these applications, although, at cold temperatures, many partial waves play a role in the scattering owing to the strong charge-neutral long-range interaction. These problems are treated mainly from a classical approach owing to a large number of partial waves present at cold temperatures for ion-neutral systems.

Rydberg physics

Rydberg physics is a classic in the atomic community. Surprisingly enough, still, it is a theme in vogue, owing to the promising applications of Rydberg atoms in quantum information systems and the recent observations of ultra-long-range Rydberg molecules. Ultra-long-Rydberg molecules appear when a Rydberg atom is immersed in a high-density ultracold gas, generally a Bose-Einstein condensate. These molecules are studied from a many-body physics approach or an atomic physics approach. However, in general, in any of these approaches, the stability of these molecules is studied. In our group, we investigate the different chemical processes that induce the decay of these molecules and hence define the lifetime of such exotic molecular bound. 

Laser cooling of molecules and ultracold chemistry

Laser cooling of atoms has revolutionized the field of atomic, molecular, and optical physics in the last decades. This technique provides the playground for a lot of intriguing phenomena, such as the Bose-Einstein condensation or quantum information. However, despite its success with atoms, it has been only recently when it has been applied to molecules.

In our group, we perform ab initio quantum chemistry calculations, and at the same time, we apply inversion techniques to get accurate potential curves from spectroscopic data. Within this approach, it is possible to identify realistically robust candidates for laser cooling of molecules.

The study of cold and ultracold processes for atom-molecule and molecule-molecule collisions is another of our interests. In particular, we are passionate about the chemistry in a buffer gas source after the ablation of a given target and about the rovibrational energy transfer for molecule-molecule collisions at ultracold temperatures. 

The general interest in the ultimate control of light-matter interaction at the single-photon level has fueled the development of photonic materials. These devices enable the strong coupling between photons and atoms employing the guided modes of the material. This new paradigm offers a unique scenario for the study of scalable quantum networks, light-matter quantum phases, and quantum metrology.

In our group, we are interested in exploiting the strong light-matter paradigm to manipulate and control light-assisted chemical reactions at ultracold temperatures, such as photo-association. In the same vein, we explore coherent control approaches to photo-association reactions, although, in our approach, we select the reactant states to lead to the desired product state.

Publications