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Updated: May 30, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Trapping cold molecular hydrogen.
Ch Seiler1, S D Hogan, F Merkt
1ETH Zurich, Laboratory of Physical Chemistry, Wolfgang Pauli-Str. 10, Zurich, Switzerland.
Physical Chemistry Chemical Physics : PCCP
|August 6, 2011
Summary
Translationally cold hydrogen molecules (H(2)) were decelerated and trapped in |M(J)| = 3 Rydberg states using electric fields. Collisions were the primary cause of trap loss, with blackbody radiation also contributing significantly.
Area of Science:
- Atomic and Molecular Physics
- Quantum Mechanics
- Laser Spectroscopy
Background:
- Rydberg states of molecules offer unique properties for manipulation.
- Controlling translationally cold molecules is crucial for precision measurements.
- Stark effect in molecular hydrogen influences Rydberg state behavior.
Purpose of the Study:
- To decelerate and trap translationally cold hydrogen molecules (H(2)) in specific Rydberg states.
- To investigate the Stark effect and avoided crossings in H(2) Rydberg states.
- To analyze and understand particle loss mechanisms in molecular trapping experiments.
Main Methods:
- Utilized time-dependent inhomogeneous electric fields for deceleration and trapping.
- Prepared |M(J)| = 3 Rydberg states via resonant three-photon excitation with circularly polarized laser radiation.
- Calculated Stark effect using matrix diagonalization and employed Monte-Carlo simulations for trajectory analysis.
Main Results:
- Successfully decelerated and trapped H(2) molecules in Rydberg states (n = 21-37).
- Monte-Carlo simulations accurately described experimental data, showing minimal loss from adiabatic crossings for n > 25.
- Identified collisional processes as the main source of trap loss, followed by blackbody radiation-induced predissociation.
Conclusions:
- Efficient trapping of H(2) in Rydberg states is achievable using electric field manipulation.
- Understanding Stark effect and avoided crossings is key to optimizing molecular trapping.
- Collisions and blackbody radiation are significant factors limiting trap lifetime for cold molecules.
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