We perform rigorous quantum mechanical calculations for collisions between magnetically trapped Eu atoms to elucidate the results of recent experimental studies. We show that the relaxation from the maximally stretched ${m}_{s}=7/2$ level is entirely determined by the magnetic dipole-dipole interaction and analyze the role of the electronic spin-exchange interaction in transitions from the lower-energy Zeeman levels. The relaxation of the ${m}_{s}=5/2$ state is shown to be very sensitive to the spin-exchange parameter that determines the splitting between the lowest electronic states of the Eu dimer. We suggest that cold collision experiments with trapped atoms can be used as a tool for obtaining accurate information on the electronic spin anisotropy in complex molecules such as Eu ${}_{2}$ .We perform rigorous quantum mechanical calculations for collisions between magnetically trapped Eu atoms to elucidate the results of recent experimental studies. We show that the relaxation from the maximally stretched ${m}_{s}=7/2$ level is entirely determined by the magnetic dipole-dipole interaction and analyze the role of the electronic spin-exchange interaction in transitions from the lower-energy Zeeman levels. The relaxation of the ${m}_{s}=5/2$ state is shown to be very sensitive to the spin-exchange parameter that determines the splitting between the lowest electronic states of the Eu dimer. We suggest that cold collision experiments with trapped atoms can be used as a tool for obtaining accurate information on the electronic spin anisotropy in complex molecules such as Eu${}_{2}$.

Physical Review AFeb 3, 201010 citations

Change of atomic spins in slow collisions

A. P. Blinov

Russian Physics JournalDec 1, 20060 citations

Spin Exchange in Slow Atomic Collisions

A. P. Blinov

Russian Physics JournalSep 1, 20050 citations

Anisotropy induced Feshbach resonances in mixture of ${}^{6}{\rm{Li}}{(}^{2}{\rm{S}})\;+\;{}^{171}{\rm{Yb}}{(}^{3}{{\rm{P}}}_{2})$ Anisotropy induced Feshbach resonances in mixture of ${}^{6}{\rm{Li}}{(}^{2}{\rm{S}})\;+\;{}^{171}{\rm{Yb}}{(}^{3}{{\rm{P}}}_{2})$

Tao Chen, Cui Zhang, Xiaolin Li +2 more

We theoretically explore the scattering properties in collisions between in the ground state and fermionic in the metastable state. Unlike the role of the electronic spin degree of freedom in collisions of two alkali-metal atoms, the orbital degrees of freedom from the p electron of the metastable atoms, which induce not only mixings between different partial waves but also couplings between channels in different fine-structure manifolds, introduce the anisotropic interactions for producing broad-enough Feshbach resonances. Our closed-coupling calculation shows that this mechanism is similar to that in highly magnetic atoms, but the resonances also suffer from a large inelastic rate at the magnitude of to lower-lying fine-structure states or Zeeman sublevels, which will be an obstacle for associating ultracold polar molecules with both electron spin and electric dipole momentum. However, such a rich mixture of inelastic processes, and the experimental advantage of immunity from intraspecies inelastic collisions for metastable fermionic allow for precise investigations on the interspecies scattering properties for systems with excited-state atoms included.We theoretically explore the scattering properties in collisions between in the ground state and fermionic in the metastable state. Unlike the role of the electronic spin degree of freedom in collisions of two alkali-metal atoms, the orbital degrees of freedom from the p electron of the metastable atoms, which induce not only mixings between different partial waves but also couplings between channels in different fine-structure manifolds, introduce the anisotropic interactions for producing broad-enough Feshbach resonances. Our closed-coupling calculation shows that this mechanism is similar to that in highly magnetic atoms, but the resonances also suffer from a large inelastic rate at the magnitude of to lower-lying fine-structure states or Zeeman sublevels, which will be an obstacle for associating ultracold polar molecules with both electron spin and electric dipole momentum. However, such a rich mixture of inelastic processes, and the experimental advantage of immunity from intraspecies inelastic collisions for metastable fermionic allow for precise investigations on the interspecies scattering properties for systems with excited-state atoms included.

New Journal of PhysicsOct 16, 20154 citations

The Theory of Atomic Collisions

F. W. Sohon

ThoughtJan 1, 193693 citations

Electron Spin Exchange in Atomic Collisions

Gary M. Carter, David E. Pritchard

We consider electron spin-exchange collisions between an atom with an electron spin of \textonehalf{} and a target atom with an arbitrary electron spin. The cross sections that describe the collision are expressed in terms of generalized direct and exchange amplitudes and are shown to depend only on the electron spin, polarization, and alignment of the target atom. We include the effects of an external magnetic field and the nuclear spin of the spin-\textonehalf{} atom on the collision. We calculate the cross sections connecting the initial and final states of the free Hamiltonian describing the spin-\textonehalf{} atom, with analytic results being displayed for the two limiting cases of the external magnetic field. For the general case, graphical results are presented for several common values of nuclear spin that allow the cross sections to be evaluated for arbitrary magnetic fields. The results are applied to several situations of current interest.We consider electron spin-exchange collisions between an atom with an electron spin of \textonehalf{} and a target atom with an arbitrary electron spin. The cross sections that describe the collision are expressed in terms of generalized direct and exchange amplitudes and are shown to depend only on the electron spin, polarization, and alignment of the target atom. We include the effects of an external magnetic field and the nuclear spin of the spin-\textonehalf{} atom on the collision. We calculate the cross sections connecting the initial and final states of the free Hamiltonian describing the spin-\textonehalf{} atom, with analytic results being displayed for the two limiting cases of the external magnetic field. For the general case, graphical results are presented for several common values of nuclear spin that allow the cross sections to be evaluated for arbitrary magnetic fields. The results are applied to several situations of current interest.

Physical Review AMar 1, 19722 citations

{m}_{s}=7/2

level is entirely determined by the magnetic dipole-dipole interaction and analyze the role of the electronic spin-exchange interaction in transitions from the lower-energy Zeeman levels. The relaxation of the

{m}_{s}=5/2

state is shown to be very sensitive to the spin-exchange parameter that determines the splitting between the lowest electronic states of the Eu dimer. We suggest that cold collision experiments with trapped atoms can be used as a tool for obtaining accurate information on the electronic spin anisotropy in complex molecules such as Eu

{}_{2}

Anisotropy induced Feshbach resonances in mixture of

{}^{6}{\rm{Li}}{(}^{2}{\rm{S}})\;+\;{}^{171}{\rm{Yb}}{(}^{3}{{\rm{P}}}_{2})