{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"bf81e884ec5c0446980f615117ffd060f22f20c6b3d3448f3341367291e8529f","created":"2026-10-03T07:17:53Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"72d13ee51bf1a9234780b476b922c144f8d088d0bff1b33c996b0ad3944a6e20","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"amo.dipolar-supersolids.lattice-supersolid","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"Magnetic atoms in an optical lattice have formed checkerboard and stripe crystals that do not flow. Theory predicts that adding or removing a few atoms should give a lattice supersolid that is both ordered and superfluid.","posed_since":"2010","precise":"Dipolar extended Bose-Hubbard model on a 2D square lattice, H = -t sum_<ij> b_i^dag b_j + (U/2) sum_i n_i(n_i - 1) + sum_i<j V_ij n_i n_j with $V_{ij} \\sim (1 - 3 \\cos^2 \\theta_{ij})/r_{ij}^3$, realized with Er or Dy atoms. Quantum Monte Carlo predicts a supersolid when the checkerboard solid is doped away from half filling (Capogrosso-Sansone et al., PRL 2010). Answer: observation of coexisting checkerboard density order and phase coherence (nonzero superfluid density) at measured filling and $T$, or a bound excluding it at accessible $V/t$.","problem_ref":null,"references":"","settled_by":"Quantum gas microscope or time-of-flight measurements showing simultaneous density-wave order and interference peaks from the same doped lattice sample.","status_note":"Checkerboard and stripe insulating solids were observed with Er in a lattice (Su et al., Nature 2023, doi:10.1038/s41586-023-06614-3), without reported superfluid coherence in the solid.","title":"Lattice supersolid of magnetic atoms in the dipolar Bose-Hubbard model","topic_ref":"e26dcf605ef7dbe6b3aca8f970b4bd57d399fcb46655381cea8a8ad67644d876"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"39c11f9a368aac39280f82e38bfa837bed155438f4a8d9a85fc87c6faa4b3790","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"975310234de347c273f9aad23a74ce77713a61af97b83c7c133e46ed796e0885","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"HucErbOTFqK5Xg24naZreSB7PcQbYIr5ZTA0-jw003pr9ckKQ3QRpt1ai6quDbk2GAV2TnV77o4oD54y8sSjCw"},"schema":"pubphys.envelope/1"},"record_hash":"39c11f9a368aac39280f82e38bfa837bed155438f4a8d9a85fc87c6faa4b3790","leaf_index":396}