Realization of a deeply subwavelength adiabatic optical lattice

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Science and Technology

Background:

• Conventional optical lattices for ultracold atoms typically have a lattice period of λ/2, where λ is the laser wavelength.
• Achieving smaller lattice periods is crucial for enhancing control and resolution in atom manipulation.

Purpose of the Study:

• To propose and demonstrate a deeply subwavelength optical lattice with a reduced period.
• To explore the creation of novel lattice structures for ultracold neutral atoms.

Main Methods:

• Utilizing N resonantly Raman-coupled internal degrees of freedom in atoms.
• Employing counterpropagating lasers with wavelength λ for two-photon Raman coupling.
• Experimentally demonstrating the lattice with a 3-state Bose-Einstein condensate of 87Rb.

Main Results:

• Achieved a lattice period of λ/(2N), an N-fold reduction compared to conventional lattices.
• Experimentally generated a lattice with a period of λ/6 (132 nm) using λ = 790 nm lasers.
• Demonstrated the conversion of the lattice into a superlattice with N wells using an additional rf-coupling field.

Conclusions:

• The proposed method enables the creation of deeply subwavelength optical lattices.
• This technique offers enhanced control over ultracold atoms for advanced quantum applications.
• The developed superlattice capability opens new avenues for quantum simulation and information processing.