January 16, 2020
A holographic approach confines excited Rydberg atoms within the central darkish area of a 3D light-intensity sample.
D. Barredo et al., Phys. Rev. Lett. (2020)
Impartial atoms in extremely excited Rydberg states could possibly be the subsequent massive factor in quantum computing, however provided that the atoms may be held in place. Optical tweezers (laser traps) can maintain ground-state atoms, however they repel Rydberg atoms, pushing them out from the brilliant point of interest of the laser beams. Now, Daniel Barredo and colleagues on the Institute of Optics in Palaiseau, France, exhibit a holographic technique that may lure particular person Rydberg atoms in 3D “lightscapes.” The crew held the atoms in place with micrometer-scale precision, a requirement for quantum-information purposes. Beforehand, 3D confinement was solely achievable with millimeter precision utilizing magnetic or electrical fields.
The researchers began with a single impartial rubidium atom, which they trapped utilizing normal optical tweezers. Deactivating the tweezers, they excited the atom to the Rydberg state. The crew then instantly recaptured the atom on the heart of a 3D light-intensity sample, created by diffracting a laser beam from a spatial gentle modulator, the place the waves interfered to type a darkish spot.
Barredo and colleagues discovered that they may maintain an excited atom for so long as the Rydberg state was maintained—about 228 𝜇s at room temperature. Throughout this time, they used microwaves to shift the atom between two Rydberg ranges, a transition that the researchers say may someday be used to characterize a qubit in a quantum laptop. The crew additionally demonstrated interactions between Rydberg atoms by making two atoms in adjoining traps change states. Such interactions are essential to create quantum logic gates.
This analysis is revealed in Bodily Overview Letters.
Marric Stephens is a contract science author based mostly in Bristol, UK.
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