Engineering Dresselhaus spin-orbit coupling for cold atoms in a double tripod configuration

TL;DR

This paper proposes a method to engineer Dresselhaus spin-orbit coupling in cold atoms using a double tripod laser configuration, resulting in robust, low-energy spin states suitable for quantum simulation.

Contribution

It introduces a novel double tripod laser setup that creates Dresselhaus SO coupling in the two lowest energy states of cold atoms, enhancing stability against collisional relaxation.

Findings

Achieved a Hamiltonian with degenerate ground states separated by Rabi frequency-dependent gaps.

Demonstrated the feasibility of implementing the scheme with Raman transitions in alkali atoms.

Provided a pathway for stable spin-orbit coupled states in cold atom systems.

Abstract

We study laser induced spin-orbit (SO) coupling in cold atom systems where lasers couple three internal states to a pair of excited states, in a double tripod topology. Proper choice of laser amplitudes and phases produces a Hamiltonian with a doubly degenerate ground state separated from the remaining "excited" eigenstates by gaps determined by the Rabi frequencies of the atom-light coupling. After eliminating the excited states with a Born- Oppenheimer approximation, the Hamiltonian of the remaining two states includes Dresselhaus (or equivalently Rashba) SO coupling. Unlike earlier proposals, here the SO coupled states are the two lowest energy "dressed" spin states and are thus immune to collisional relaxation. Finally, we discuss a specific implementation of our system using Raman transitions between different hyperfine states within the electronic ground state manifold of nuclear spin I = 3/2 alkali atoms.