The spectrum is investigated using proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of , collected by the LHCb experiment during 2016–2018. Four states are observed with high significance, and their masses and widths are measured to be , , , , , , , , where the uncertainties are statistical, systematic, and due to the limited precision on the mass, respectively. The baryon is observed for the first time, and is consistent with being the isospin partner of the previously observed state. Most of the measured parameters are more precise than existing world averages.
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Strongly Interacting, Two-Dimensional, Dipolar Spin Ensembles in (111)-Oriented Diamond
Systems of spins with strong dipolar interactions and controlled dimensionality enable new explorations in quantum sensing and simulation. In this work, we investigate the creation of strong dipolar interactions in a two-dimensional ensemble of nitrogen-vacancy (NV) centers generated via plasma-enhanced chemical vapor deposition on (111)-oriented diamond substrates. We find that diamond growth on the (111) plane yields high incorporation of spins, both nitrogen and NV centers, where the density of the latter is tunable via the miscut of the diamond substrate. Our process allows us to form dense, preferentially aligned, 2D NV ensembles with volume-normalized ac sensitivity down to . Furthermore, we show that (111) affords maximally positive dipolar interactions among a 2D NV ensemble, which is crucial for leveraging dipolar-driven entanglement schemes and exploring new interacting spin physics.
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- Award ID(s):
- 2317134
- PAR ID:
- 10688253
- Publisher / Repository:
- Physical Review X
- Date Published:
- Journal Name:
- Physical Review X
- Volume:
- 15
- Issue:
- 2
- ISSN:
- 2160-3308
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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