CsAg – UltraMeDiQs

Motivation
 

Ultracold atoms and molecules are particularly well suited to create and study quantum matter. However, so far, this was essentially limited to quantum gases and quantum liquids, in which collisions between the particles are limited to two colliding particles. When three or more particles come too close, they form a classical molecule and the control over the quantum properties is lost. However, with di-atomic molecules that have an uneven charge distribution (dipolar molecules) a particular interaction between the molecules can be engineered through quantum physics, which keeps the molecules so far separate that they can't undergo classical reactions ('shielding'). Particularly heavy molecules with a particularly large charge distribution feature an interaction that is so strong it enables the construction of these 'solid' quantum clusters and quantum crystals.

Why CsAg?
 

Cesium–Silver molecules (CsAg) feature one of the largest possible electrical dipole moments and the interaction between them can be much stronger than for all ultracold molecules that are available, so far. The interaction should be strong enough to form the sought-after quantum crystals.

The Roadmap
 

First, we cool cesium and silver atoms with the help of lasers (laser cooling) to ultracold temperatures to gain full control over their quantum states. Afterwards, we use quantum effects to form CsAg molecules from the individual atoms with maximal quantum control. For this purpose, we utilize optical tweezers made out of tightly focused laser beams. This is a technique that usually finds application in modern quantum computers. The optical tweezers and optical laser lattices enable us to assemble quantum clusters and quantum crystals from the ultracold molecules.

Challenge – Silver
 

Although, in 2000, silver atoms have been laser cooled for the first time, there is still very little experience in the creation of ultracold silver samples. Therefore, we have formed a 'silver-alliance' with other international research groups, who also aim to bind silver atoms in ultracold molecules, to overcome the technical challenges, together.

Funding
 

This work is supported by ERC grant UltraMeDiQs (Projekt Nr. 101219560, opens an external URL in a new window).

Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.

CaF
 

A project with directly laser-cooled Calcium monofluoride. For more details, see coldmolecules.eu, opens an external URL in a new window.