We present a rigorous quantum study of spin-exchange transitions in collisions of the alkali-metal atoms with $^{3}\text{H}\text{e}$ in the presence of an external magnetic field. Using accurate ab initio interaction potentials, we obtain refined estimates for the Fermi contact interaction constants for complexes of Na, K, and Rb atoms with $^{3}\text{H}\text{e}$ . Ab initio calculations show that the Fermi contact interaction in $\text{Li-}^{3}\text{H}\text{e}$ varies more slowly with internuclear distance than predicted by the atomic model [R. M. Herman, Phys. Rev. 37, A1062 (1965)]. The calculated spin-exchange rate constants for Na, K, and Rb atoms in a gas of $^{3}\text{H}\text{e}$ are in good agreement with experimental data. Our calculations demonstrate that at a temperature of 0.5 K, collision-induced spin exchange of the alkali-metal atoms occurs at a very slow rate of $\ensuremath{\sim}{10}^{\ensuremath{-}22}\text{ }{\text{cm}}^{3}/\text{s}$, suggesting potential applications in cryogenic cooling, precision spectroscopy, and quantum optics.We present a rigorous quantum study of spin-exchange transitions in collisions of the alkali-metal atoms with $^{3}\text{H}\text{e}$ in the presence of an external magnetic field. Using accurate ab initio interaction potentials, we obtain refined estimates for the Fermi contact interaction constants for complexes of Na, K, and Rb atoms with $^{3}\text{H}\text{e}$. Ab initio calculations show that the Fermi contact interaction in $\text{Li-}^{3}\text{H}\text{e}$ varies more slowly with internuclear distance than predicted by the atomic model [R. M. Herman, Phys. Rev. 37, A1062 (1965)]. The calculated spin-exchange rate constants for Na, K, and Rb atoms in a gas of $^{3}\text{H}\text{e}$ are in good agreement with experimental data. Our calculations demonstrate that at a temperature of 0.5 K, collision-induced spin exchange of the alkali-metal atoms occurs at a very slow rate of $\ensuremath{\sim}{10}^{\ensuremath{-}22}\text{ }{\text{cm}}^{3}/\text{s}$, suggesting potential applications in cryogenic cooling, precision spectroscopy, and quantum optics.

Physical Review AJun 9, 200925 citations

Collision-induced spin depolarization of alkali-metal atoms in cold He3 gas

Timur V. Tscherbul, P. Zhang, H. R. Sadeghpour +4 more

We present a joint experimental and theoretical study of spin depolarization in collisions of alkali-metal atoms with $^{3}\mathrm{He}$ in a magnetic field. A rigorous quantum theory for spin-changing transitions is developed and applied to calculate the spin exchange and spin relaxation rates of Li and K atoms in cryogenic $^{3}\mathrm{He}$ gas. Magnetic trapping experiments provide upper bounds to the spin exchange rates for $\mathrm{Li}\text{\ensuremath{-}}^{3}\mathrm{He}$ and $\mathrm{K}\text{\ensuremath{-}}^{3}\mathrm{He}$, which are in agreement with the present theory. Our calculations demonstrate that the alkali-metal atoms have extremely slow spin depolarization rates, suggesting a number of potential applications in precision spectroscopy and quantum optics.We present a joint experimental and theoretical study of spin depolarization in collisions of alkali-metal atoms with $^{3}\mathrm{He}$ in a magnetic field. A rigorous quantum theory for spin-changing transitions is developed and applied to calculate the spin exchange and spin relaxation rates of Li and K atoms in cryogenic $^{3}\mathrm{He}$ gas. Magnetic trapping experiments provide upper bounds to the spin exchange rates for $\mathrm{Li}\text{\ensuremath{-}}^{3}\mathrm{He}$ and $\mathrm{K}\text{\ensuremath{-}}^{3}\mathrm{He}$, which are in agreement with the present theory. Our calculations demonstrate that the alkali-metal atoms have extremely slow spin depolarization rates, suggesting a number of potential applications in precision spectroscopy and quantum optics.

Physical Review ADec 31, 200816 citations

The Role of Electron Spin in Atomic Collisions

Wolfgang Jitschin

NATO ASI series. Series B : PhysicsJan 1, 19850 citations

Magnetic Slowing Down of Spin Relaxation due to Binary Collisions of Alkali-Metal Atoms with Buffer-Gas Atoms

D. K. Walter, W. M. Griffith, W. Happer

We report the first studies of magnetic decoupling of the spin relaxation of alkali-metal atoms due to binary collisions with buffer gases. When binary collisions are the dominant relaxation mechanism, the relaxation and its magnetic decoupling are well described by the $S$ -damping rate ${\ensuremath{\Gamma}}_{\mathrm{SD}}$ due to the spin-rotation interaction $\ensuremath{\gamma}\mathbf{N}\ifmmode \dot{}\else \.{}\fi{}\mathbf{S}$, the spin exchange rate ${\ensuremath{\Gamma}}_{\mathrm{EX}}$ for collisions between alkali atoms, and a new ``Carver rate'' ${\ensuremath{\Gamma}}_{\mathrm{C}}$, due to the pressure-shift interaction $\ensuremath{\delta}A\mathbf{I}\ifmmode \dot{}\else \.{}\fi{}\mathbf{S}$, which can substantially broaden the magnetic decoupling curve while having no influence on the zero-field rates.We report the first studies of magnetic decoupling of the spin relaxation of alkali-metal atoms due to binary collisions with buffer gases. When binary collisions are the dominant relaxation mechanism, the relaxation and its magnetic decoupling are well described by the $S$-damping rate ${\ensuremath{\Gamma}}_{\mathrm{SD}}$ due to the spin-rotation interaction $\ensuremath{\gamma}\mathbf{N}\ifmmode \dot{}\else \.{}\fi{}\mathbf{S}$, the spin exchange rate ${\ensuremath{\Gamma}}_{\mathrm{EX}}$ for collisions between alkali atoms, and a new ``Carver rate'' ${\ensuremath{\Gamma}}_{\mathrm{C}}$, due to the pressure-shift interaction $\ensuremath{\delta}A\mathbf{I}\ifmmode \dot{}\else \.{}\fi{}\mathbf{S}$, which can substantially broaden the magnetic decoupling curve while having no influence on the zero-field rates.

Physical Review LettersFeb 15, 200237 citations

INELASTIC COLLISIONS OF SLOW ATOMS

Борис М. Смирнов

Oct 1, 19640 citations

We present a rigorous quantum study of spin-exchange transitions in collisions of the alkali-metal atoms with

^{3}\text{H}\text{e}

in the presence of an external magnetic field. Using accurate ab initio interaction potentials, we obtain refined estimates for the Fermi contact interaction constants for complexes of Na, K, and Rb atoms with

^{3}\text{H}\text{e}

. Ab initio calculations show that the Fermi contact interaction in

\text{Li-}^{3}\text{H}\text{e}

varies more slowly with internuclear distance than predicted by the atomic model [R. M. Herman, Phys. Rev. 37, A1062 (1965)]. The calculated spin-exchange rate constants for Na, K, and Rb atoms in a gas of

^{3}\text{H}\text{e}

are in good agreement with experimental data. Our calculations demonstrate that at a temperature of 0.5 K, collision-induced spin exchange of the alkali-metal atoms occurs at a very slow rate of $\ensuremath{\sim}{10}^{\ensuremath{-}22}\text{ }{\text{cm}}^{3}/\text{s}$, suggesting potential applications in cryogenic cooling, precision spectroscopy, and quantum optics.

We present a joint experimental and theoretical study of spin depolarization in collisions of alkali-metal atoms with

^{3}\mathrm{He}

in a magnetic field. A rigorous quantum theory for spin-changing transitions is developed and applied to calculate the spin exchange and spin relaxation rates of Li and K atoms in cryogenic

^{3}\mathrm{He}

gas. Magnetic trapping experiments provide upper bounds to the spin exchange rates for $\mathrm{Li}\text{\ensuremath{-}}^{3}\mathrm{He}$ and $\mathrm{K}\text{\ensuremath{-}}^{3}\mathrm{He}$, which are in agreement with the present theory. Our calculations demonstrate that the alkali-metal atoms have extremely slow spin depolarization rates, suggesting a number of potential applications in precision spectroscopy and quantum optics.

S

-damping rate ${\ensuremath{\Gamma}}_{\mathrm{SD}}$ due to the spin-rotation interaction $\ensuremath{\gamma}\mathbf{N}\ifmmode \dot{}\else \.{}\fi{}\mathbf{S}$, the spin exchange rate ${\ensuremath{\Gamma}}_{\mathrm{EX}}$ for collisions between alkali atoms, and a new ``Carver rate'' ${\ensuremath{\Gamma}}_{\mathrm{C}}$, due to the pressure-shift interaction $\ensuremath{\delta}A\mathbf{I}\ifmmode \dot{}\else \.{}\fi{}\mathbf{S}$, which can substantially broaden the magnetic decoupling curve while having no influence on the zero-field rates.