Bichromatic UV detection system for atomically-resolved imaging of ions

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Information Science
• Spectroscopy

Background:

• Trapped ion systems are crucial for quantum computing and precision measurements.
• Simultaneous imaging of multiple ion species is challenging due to differing optical properties.
• Existing methods often lack resolution or the ability to image across different wavelengths effectively.

Purpose of the Study:

• To develop a compact, external bichromatic imaging system for simultaneous, ion-resolved imaging of dual-species trapped ion crystals.
• To overcome limitations in imaging deep ultraviolet (230.6 nm) and visible (369.5 nm) wavelengths simultaneously.
• To enable spatially resolved state detection for long Coulomb crystals of 115In+ and 172Yb+ ions.

Main Methods:

• Designed a compact optical system with two lens doublets (sphere and asphere) placed outside the vacuum chamber.
• Utilized a shared electron-multiplying charge-coupled device (EMCCD) camera for simultaneous photon collection.
• Achieved numerical apertures of 0.45 (230.6 nm) and 0.40 (369.5 nm) with a 300 μm field of view.

Main Results:

• Demonstrated simultaneous, single-ion resolved imaging of 115In+ and 172Yb+ ions.
• Achieved high-quality imaging at 230.6 nm, addressing challenges with deep UV light and low In+ ion scattering.
• Enabled spatially resolved state detection over a large field of view for Coulomb crystals.

Conclusions:

• The presented bichromatic imaging system offers a versatile and effective solution for dual-species trapped ion applications.
• This approach overcomes previous limitations in simultaneous multi-wavelength imaging, particularly for deep UV wavelengths.
• The concept is broadly applicable to other dual-species ion trapping experiments and quantum technologies.