{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"dddebf391ce81667a47043d8d04942f56f4bd53d6e1d0c1534b90a08dec8fa78","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["0be1571f7ace75f1838533f2cfcdad0cd14a7bbdf1ff1ffcad2fda87064fae84","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"714c9bbf3e08c50e79bec780bc904e8aae8a841b77506590d3f600e240e11c15","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"cm.quantum-spin-glasses.lihoyf-glass-phase","kind":"well-posed","literature_status":"contested","n":"2","parents":[],"plain":"$\\mathrm{LiHoYF_4}$ is a crystal in which magnetic holmium ions are diluted by nonmagnetic yttrium, and a sideways field adds quantum fluctuations. Experiments disagree on whether its low-temperature state is a genuine spin glass, so it is unclear whether it realizes a quantum spin-glass transition.","posed_since":"","precise":"In LiHo_xY_1-xF4 with x of about 0.17 to 0.2 (dipolar Ising moments along c, transverse field $H_t$ perpendicular to c), determine whether the nonlinear susceptibility diverges at a finite $T_g(H_t)$ and whether $T_g(H_t)$ ends at a $T = 0$ quantum critical point, given the random longitudinal fields generated by $H_t$ and the hyperfine coupling to Ho nuclei. An answer is a measured phase boundary with critical exponents, or evidence that no thermodynamic glass transition exists.","problem_ref":"0be1571f7ace75f1838533f2cfcdad0cd14a7bbdf1ff1ffcad2fda87064fae84","references":"","settled_by":"Equilibrium nonlinear ac susceptibility and noise measurements below 0.1 K on samples of controlled x, analyzed by critical scaling and compared with Monte Carlo of the dipolar model including hyperfine terms.","status_note":"Jonsson et al. (PRL 2007) reported no glass transition at $x = 0.167$ while Ancona-Torres et al. (PRL 2008) reported one; field-induced random fields complicate the transverse-field phase diagram.","title":"Does LiHo_xY_1-xF4 have a true spin-glass phase and quantum transition?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"3255691e90c403ce5fe2ab30ed26ef5c80fb32a1948d034cf8be7078c1886efe","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"cf71c1367af7af2c18b9b8683adb951f1119f7ba88b8d023a09fc2ca901e788b","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"ctaLW8-yi9IinCQ9rd-BTlPZk8s5CvanihKgS58C6OA36s_eKW4hE08gBMJqYGAqZ1vTXvQXVWi9Ymm-Dp3FCw"},"schema":"pubphys.envelope/1"},"record_hash":"3255691e90c403ce5fe2ab30ed26ef5c80fb32a1948d034cf8be7078c1886efe","leaf_index":3000}