Fate of the three-boson Efimov spectrum in the presence of one-dimensional spin-orbit coupling

Qi Zhou, Xiaoling Cui

Q. Guan, D. Blume

A new theoretical analysis shows that the unique radial scaling law of the Efimov effect---in which three bosons form a sequence of uniquely related bound trios---survives in the presence of one-dimensional spin-orbit coupling even though multiple length scales exist in the system.

Yusuke Nishida

Qingze Guan, D. Blume

It was shown recently that the discrete scaling symmetry, which underlies the Efimov effect in the three identical boson system with two-body short-range interactions, survives when single-particle one-dimensional (1D) spin-orbit coupling terms are added to the Hamiltonian. Each three-body energy level in the ordinary Efimov scenario turns into an energy manifold that contains four energy levels in the presence of 1D spin-orbit coupling (equal mixture of Rashba-Dresselhaus coupling). This work provides a detailed characterization of the energy levels in these manifolds. The two-boson energies, which enter into the three-boson scattering threshold, are analyzed in detail. Moreover, the structural properties, e.g., momentum distributions of the two- and three-boson systems, are analyzed for various parameter combinations.

Arnoldas Deltuva

Qing Ji, Ren Zhang, Wei Zhang

We exactly solve the two-body and three-body problems in the mixture of alkaline-earth-metal(like) (AE) and alkali-metal atomic gases in the presence of three-dimensional isotropic spin-orbit (SO) coupling. The SO coupling is implemented by the Raman scheme that couples the ground state of the AE atom with different nuclear spin. The interaction between AE and alkali-metal atoms is tuned to be near resonant by Feshbach resonance, while the interaction between the two AE atoms is negligible. We present the Skorniakov--Ter-Martirosian (STM) equation for the three-body system composed of two SO coupled AE atoms and one alkali-metal atom. By solving the STM equation in the zero angular momentum sector, we obtain the energy spectrum and find a nonuniversal Efimov trimer and a universal Kartavtsev-Malykh (KM) trimer in different parameter windows of the mass ratio. In the region where the KM trimer is present, strong SO coupling can stabilize the KM trimer to be the ground state, such that experimental realization and observation can be expected.