{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"c9c227c7b8db329a03a769b67933563130d81f341710957d7cef03653d206de8","created":"2026-10-03T07:18:00Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"9c67a450e8b459fe9cbe773c38adc808987af1c750921b60b06c87bccb1af330","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"cm.majorana-zero-modes.shiba-chains","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Chains of iron atoms on superconducting lead show zero-energy states at their ends that were proposed as Majorana modes, but ordinary bound states can look similar, and the identification is unsettled.","posed_since":"2014","precise":"STM on Fe atomic chains on Pb(110) (Nadj-Perge et al., Science 346, 602, 2014, doi:10.1126/science.1259327) and on later chains assembled atom by atom on superconductors shows zero-bias features at chain ends. Determine whether these are Majorana zero modes of a topological band of hybridized Yu-Shiba-Rusinov states (bound states induced by magnetic atoms in a superconductor). Required: a resolved bulk topological gap larger than the end-mode splitting, splitting that decays exponentially with chain length, and zero-bias conductance $2e^{2}/h$ in the strong-coupling tunnelling limit. An answer is yes or no for a specified chain system.","problem_ref":null,"references":"","settled_by":"Length-dependent spectroscopy on atom-by-atom assembled chains showing exponential decay of end-mode splitting with a resolved topological gap.","status_note":"Trivial interpretations of the end states are not excluded as of 2026, to this survey's knowledge.","title":"Are end states of magnetic atom chains on superconductors Majorana modes","topic_ref":"22b1c284f405dca649b67435bdabcd2fe6cb89dca2e57c0dd9c49b870c73940e"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"5be4755edd3b1b836dd23e6509a783007913ac591e3e966ecae604a0bc82197e","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"9d271c27b764cc591ea93b2fefdf6f7a7cf15c9f96981e2b2e754e69d54c0ba3","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"2kV_oQOOZPdgCGSb_sCaM1fQMk1VqmTBiQ2bKzpy_vIpN7x8xHC9rFEqUyc6snsgTf6x8BcxNQLi1bZ490kXDA"},"schema":"pubphys.envelope/1"},"record_hash":"5be4755edd3b1b836dd23e6509a783007913ac591e3e966ecae604a0bc82197e","leaf_index":1083}