Related Experiment Video
Updated: Jun 21, 2025

Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Long-Lived Coherence on a μHz Scale Optical Magnetic Quadrupole Transition
V Klüsener1,2, S Pucher1,2, D Yankelev1,2
1<a href="https://ror.org/01vekys64">Max-Planck-Institut für Quantenoptik</a>, 85748 Garching, Germany.
Abstract:
We report on the coherent excitation of the ultranarrow ^{1}S_{0}-^{3}P_{2} magnetic quadrupole transition in ^{88}Sr. By confining atoms in a state insensitive optical lattice, we achieve excitation fractions of 97(1)% and observe linewidths as narrow as 58(1) Hz. With Ramsey spectroscopy, we find coherence times of 14(1) ms, which can be extended to 266(36) ms using a spin-echo sequence. We determine the lifetime of the ^{3}P_{2} level for spontaneous emission of magnetic quadrupole radiation to be 110(31) min, confirming long-standing theoretical predictions. These results establish an additional clock transition in strontium and pave the way for applications of the metastable ^{3}P_{2} state in quantum computing and quantum simulations.
Related Concept Videos
Atomic Nuclei: Nuclear Relaxation Processes
Atomic Nuclei: Larmor Precession Frequency
NMR Spectroscopy: Spin–Spin Coupling
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
Atomic Nuclei: Magnetic Resonance
UV–Vis Spectroscopy: Molecular Electronic Transitions

