Fig. 1: Microwave shielding.
From: Evaporation of microwave-shielded polar molecules to quantum degeneracy
a, Sketch of the experimental set-up. The molecules are confined by up to three optical dipole traps with the indicated wavelengths. A helical antenna emits the rotating electric field E. A d.c. magnetic offset field B is generated by a pair of coils (not shown). b, Preparation of the molecules in the dressed state \(|+\rangle \). The microwave detuning Δ is typically comparable to the Rabi frequency Ω. c, Interaction potentials for Δ = 2π × 8 MHz and Ω = 2π × 11 MHz. The solid and dashed lines show the potential energy of molecules colliding along (θ = 0) and orthogonal (θ = 90°) to the microwave propagation direction, respectively. The centrifugal barrier is omitted for clarification. The arrow illustrates an elastic collision. Here, a0 is the Bohr radius. d, Close-up of the shielded collisional channel \(|\,++\,\rangle \). The insets show the alignment of the rotating molecules with respect to each other. At intermediate range, the molecules align with respect to the intermolecular axis.
