Strontium in optical lattices

Ultracold strontium is well-known for its use in highly accurate optical lattice clocks [1-4]. However, in recent years the high measurement precision afforded by strontium has led to a new class of experiments, which use the techniques of atomic clocks to realize novel many-body states [5] and exotic quantum effects [6,7].

Although ultracold strontium is capable of extraordinary measurement precision [8], it lacks the long-range interactions that are the foundation of many exciting new experiments [9-12]. Fortunately atoms can be endowed with strong, long-range interactions by coupling them to Rydberg states [13]. The Rydberg interaction has been used in neutral atoms to demonstrate entanglement [14], quantum gates [13], and interesting many-body effects like Rydberg spatial ordering and Ising crystallization [15,16].

The aim of this project is to combine the precision of atomic clocks with long-range interactions using Rydberg states. This experiment is based on a low-entropy gas of strontium confined in a 2D lattice potential and dressed by a Rydberg state. Rydberg dressing allows the interaction strength to be tunable [17], and the system is also designed with the ability to address lattice sites independently. These ingredients result in an apparatus that can precisely control the quantum states and interaction strength of every atom.

Such a high degree of control could enable numerous applications, but we primarily focus on quantum information and quantum simulation.


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