Molecular lattice clock with long vibrational coherence

Abstract

Atomic lattice clocks have spurred numerous ideas for tests of fundamental physics, detection of general relativistic effects, and studies of interacting many-body systems. On the other hand, molecular structure and dynamics offer rich energy scales that are at the heart of new protocols in precision measurement and quantum information science. Here we demonstrate a fundamentally distinct type of lattice clock that is based on vibrations in diatomic molecules, and present coherent Rabi oscillations between weakly and deeply bound molecules that persist for 10's of milliseconds. This control is made possible by a state-insensitive magic lattice trap that weakly couples to molecular vibronic resonances and enhances the coherence time between molecules and light by several orders of magnitude. The achieved quality factor Q = 8 × 10 11 results from 30-Hz narrow resonances for a 25-THz clock transition in Sr2. Our technique of extended coherent manipulation is applicable to long-term storage of quantum information in qubits based on ultracold polar molecules, while the vibrational clock enables precise probes of interatomic forces, tests of Newtonian gravitation at ultrashort range, and model-independent searches for electron-to-proton mass ratio variations.

Polyatomic molecules as quantum sensors for fundamental physics

“…Two vibrational levels in different potential energy surfaces have a small energy splitting and different dependence on ω v ∝ µ −1/2 , and therefore a large enhancement factor. molecular clocks to probe the changing vibrational energy splittings directly, without relying on accidental near-degeneracies [1, 155,168,169].…”

Observation of electric-quadrupole infrared transitions in water vapor

“…Quadrupole electronic and ro-vibrational transitions have been detected in a number of atoms [1,2] and homonuclear diatomic molecules [3,4,5], respectively, for states that cannot undergo electric dipole transitions. When compared with dipole transitions, quadrupole transition rates are typically smaller by a factor ranging from 10 8 in the IR to 10 5 in the optical spectral domain.…”

Weakly bound molecules as sensors of new gravitylike forces

“…This, however, will also require the inclusion of several subtle QED and relativistic effects 26,32,34 in the theoretical description of long range atomic interactions. If data for many isotopes are to be used 35,36 an ab initio calculation of isotope-dependent corrections, like the adiabatic, nonadiabatic or nuclear volume corrections 28 may prove necessary. Although our method only tests the presence of a Yukawa-type potential, in the future, the mass-dependency of Yukawa gravitylike forces could additionally constrain their magnitude, through its impact on the mass-scaling behavior of the near-threshold bound state positions between different isotopes.…”