{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"91d529b17893ad9c43ba6e19a3174408ca785958a315c8f71e09ff28e6ff0711","created":"2026-10-03T07:18:01Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"7574a41242d243a76b73ad030f6fc101ba3ff43d76d9420ebfc584e528755994","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"cm.spin-ice.emergent-photon-evidence","kind":"phenomenon","literature_status":"partially-resolved","n":"1","parents":[],"plain":"Quantum spin ice should host three kinds of emergent particles: photons, electric-like spinons and magnetic monopoles. Cerium pyrochlores such as Ce2Zr2O7 show signs of these, but alternative explanations are not fully excluded.","posed_since":"2004","precise":"In Ce2Zr2O7, Ce2Sn2O7 and Ce2Hf2O7 (dipolar-octupolar doublets), establish the $\\mathrm{U}(1)$ quantum spin liquid through its distinct signatures: a gapless linearly dispersing transverse photon ($C \\sim T^{3}$ well below the photon bandwidth), a spinon continuum, and their predicted spectral weights. An answer is a fit of thermodynamic and neutron data by quantum spin ice theory with independently fixed exchange parameters that excludes classical or disorder-driven alternatives.","problem_ref":null,"references":"","settled_by":"Polarized neutron scattering below $0.05\\,\\mathrm{K}$ resolving the low-energy photon mode and heat capacity showing the $T^3$ term, both matched to quantum Monte Carlo of the fitted XYZ model.","status_note":"Gao et al. (Nature Physics 2025) reported neutron and thermodynamic evidence for emergent photons and spinons in Ce2Zr2O7, interpreted as a pi-flux quantum spin ice.","title":"Has emergent quantum electrodynamics been observed in a quantum spin ice?","topic_ref":"52cddd9c3d75748e46e41f34a20edd20c81c928cc0056fa7e4de59ade0220e82"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"692e84275354594b030e926ee9b76c7f88ecf4490783f075252d14127adb8d67","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"3e47777001f2ebf472dbe44c1f90e356373cc620ecfafed4d8cd1543b5f9c338","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"UVvrBwsEyeXMVtUreASYwaVty6eae7HAw14mg8ZCTTlr5h6_bJroH2GCN8grLKKPEdWfWhcpe6xyzgQdgQfPDw"},"schema":"pubphys.envelope/1"},"record_hash":"692e84275354594b030e926ee9b76c7f88ecf4490783f075252d14127adb8d67","leaf_index":1170}