Resonant manipulation ofd-wave interaction of cold atoms with two lasers and a magnetic field

Abstract

We present a theory for manipulation of d-wave interaction of cold atoms with two lasers strongly driving two photoassociative transitions. The theory predicts the occurrence of a coherence between two excited ro-vibrational bound states due to the photoassociative dipole couplings of ground-state d-wave scattering state to the bound states. We show that this excited-state coherence significantly influences atom-atom interaction. In particular, this leads to the enhancement of d-wave elastic scattering and to the suppression of inelastic scattering. In the presence of an s-wave magnetic Feshbach resonance, the two lasers can couple the s-wave resonance with the d-wave scattering state, leading to the further enhancement in d-wave scattering at relatively low energy. Our numerical calculations based on realistic parameters show that d-wave manipulation would be most effective in case of atoms having excited diatomic states with narrow natural linewidth. We estimate that at an energy of 100 μK the inelastic scattering rate in Yb can be reduced to 20 s −1 while the elastic scattering rate can be two orders of magnitude larger.

Decay dynamics in a strongly driven atom–molecule coupled system

“…The polarizations of both lasers are assumed to be the same. This geometry is the same as used in [18] for manipulation of d-wave atom-atom interactions.…”

“…the transition dipole moment between the nth excited bound state and the ground bound state |b 0 , σ the polarization of the field and √ ω κ /2 0 V the amplitude of the vacuum field and ω b 0 is the binding energy of the bound state |b 0 . The Hamiltonian H coh is exactly diagonalizable [13,18] in the spirit of Fano's theory [4]. The eigenstate of H S is a dressed continuum expressed as…”

“…with the normalization condition dr E |E dr = δ(E −E ). The coefficients A nE and C E (E ) are derived in [18].…”

Formation of a molecular ion by photoassociative Raman processes

“…As a further study, one can consider twophoton Raman process involving a magnetic Feshbach-resonance induced structured continuum [57]. In such physical situations, it is possible to create a bound state in continuum that can be effectively decoupled from the continuum [58]. This opens up the possibility of creating an effective Λ system of three bound states involving an underlying continuum.…”

Manipulating nanoscale atom–atom interactions with cavity QED

“…| ( )| is the width of the bound state due to nonadiabatic coupling. Following [48], we obtain the T matrix element…”