Mechanism of Collisional Spin Relaxation in Triplet-Sigma Molecules

Abstract

We measure and theoretically determine the effect of molecular rotational splitting on Zeeman relaxation rates in collisions of cold Triplet-Sigma molecules with helium atoms in a magnetic field. All four stable isotopomers of the imidogen (NH) molecule are magnetically trapped and studied in collisions with 3He and 4He. The 4He data support the predicted inverse square dependence of the collision induced Zeeman relaxation rate coefficient on the molecular rotational constant B. The measured 3He rate coefficients are much larger than 4He and depend less strongly on B, and the theoretical analysis indicates they are strongly affected by a shape resonance. The results demonstrate the influence of molecular structure on collisional energy transfer at low temperatures.

arXiv comment10 pages, 3 figures, revised introduction and focus

References in corpus (5)

• Quantum computation with trapped polar molecules
• Molecules Near Absolute Zero and External Field Control of Atomic and Molecular Dynamics
• Quantum fluids of self-assembled chains of polar molecules
• Magnetic trapping and Zeeman relaxation of imidogen (NH X-triplet-Sigma)
• Long range scattering resonances in strong-field seeking states of polar molecules

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