Collisions of Polar Molecules with Ultracold Alkali Metal Atoms (IP3 of EuroQUAM CoPoMol)
Lead Research Organisation:
Imperial College London
Department Name: Physics
Abstract
Using laser cooling techniques, it is possible to cool atoms to extremely low temperatures. However, this technique cannot be applied directly to cool molecules because of the complex internal structure that molecules possess. Nevertheless, there is currently a great desire to cool molecules, particularly polar molecules which bring long-range interactions into the cold gas. One very promising approach to producing ultracold molecules is to trap molecules together with ultracold atoms. The molecules then collide with the atoms which act like a refrigerant - a process known as sympathetic cooling.To achieve sympathetic cooling there are many obstacles to overcome. The best way to proceed is to work together with other researchers to tackle the numerous challenges. Not least of these is the problem of working out how many atom-molecule and molecule-molecule collisions there will be per unit time, and understanding what happens in these collisions. This difficult problem requires a combined experimental and theoretical effort. We will also need to work out how atoms and molecules can be stored in the same trap for sufficiently long periods of time, how to prevent them from leaving the trap and how to measure their temperatures. This research brings together experts from around Europe who will collaborate to solve these experimental and theoretical problems and thereby form ultracold polar molecules.
Organisations
People |
ORCID iD |
Michael Tarbutt (Principal Investigator) |
Publications
Tokunaga S
(2011)
Prospects for sympathetic cooling of molecules in electrostatic, ac and microwave traps
in The European Physical Journal D
Tokunaga S
(2009)
Stark deceleration of lithium hydride molecules
in New Journal of Physics
Wall T
(2010)
Nonadiabatic transitions in a Stark decelerator
in Physical Review A
Description | Through this grant, we developed a molecular decelerator based on the interaction of molecules with electric fields. We used this decelerator to slow down a beam of lithium hydride molecules from an initial speed of 420m/s to a final speed of 50m/s. We also learned how to control the rotational motion of these molecules. This work extends the methods for manipulating and controlling the motion of atoms and molecules to new, interesting species. We then investigated how the lithium hydride molecules could be cooled to extremely low temperatures. This is important for investigating and controlling quantum interactions between molecules, since control at the quantum level only becomes possible when all random thermal motion is removed by cooling to low temperature. We investigated how molecules could be cooled through their collisions with very cold atoms, a process known as sympathetic cooling. For this to work, warm molecules and cold atoms have to be confined together for long periods of time in a suitable trap. We discovered that existing electric and magnetic traps are not suitable environments for sympathetic cooling, but that a new kind of trap based on microwave fields is suitable. |
Exploitation Route | Others will be able to follow our work on the deceleration of molecules and extend it to other, more complex species. Those interested in cooling molecules to very low temperatures will wish to follow our findings on the suitable environment for sympathetic cooling. |
Sectors | Education,Other |
URL | http://www3.imperial.ac.uk/ccm/research/coldmol |
Description | The impact has been in the academic community. |
Description | EPSRC |
Amount | £6,349,250 (GBP) |
Funding ID | EP/I012044/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start |
Description | EPSRC |
Amount | £6,349,250 (GBP) |
Funding ID | EP/I012044/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start |
Description | Laser cooling molecules |
Amount | £720,518 (GBP) |
Funding ID | EP/H031103/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start | 04/2010 |
End | 09/2013 |
Description | Microkelvin molecules in a quantum array |
Amount | £6,380,561 (GBP) |
Funding ID | EP/I012044/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start | 12/2010 |
End | 03/2016 |
Description | Production of cold, heavy molecules at rest. |
Amount | £555,840 (GBP) |
Funding ID | EP/F035160/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start | 04/2008 |
End | 10/2011 |