{
  "abstract": "Adiabatic demagnetization refrigeration (ADR) based on frustrated rare-earth magnets provides a promising route toward helium-free sub-Kelvin cooling, while balancing magnetic entropy and interaction scales is essential for optimizing the ADR functionalities. Here we investigate the low-temperature magnetic and ADR properties of the alkali rare-earth double phosphates K$_3$$Ln$(PO$_4$)$_2$ ($Ln$ = Yb, Gd), which crystallize in a monoclinic $P2_1/m$ structure containing distorted isosceles triangular lattices of rare-earth ions. Magnetization and specific heat measurements confirm the absence of long-range magnetic ordering down to 0.1 K in both compounds. Direct quasi-ADR measurements demonstrate strongly contrasting refrigeration behaviors: K$_3$Yb(PO$_4$)$_2$ reaches a minimum temperature of 29.8 mK from an initial state of 2 K and 6 T, whereas K$_3$Gd(PO$_4$)$_2$ exhibits extended hold times below 150 mK associated with its larger magnetic entropy reservoir. Crystal-electric-field calculations confirm a $J_{\\mathrm{eff}} = 1/2$ ground-state doublet in K$_3$Yb(PO$_4$)$_2$, while thermodynamic analysis based on magnetic entropy and interaction scales accounts for the distinct ADR performance of the two compounds. These results identify K$_3$$Ln$(PO$_4$)$_2$ as a chemically robust platform for rare-earth-tunable solid-state ADR.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Physical Review B 114, 214419 (2026)",
  "arxiv": "2610.28038",
  "author_total": 11,
  "authors": [
    {
      "name": "Yonglin Wang"
    },
    {
      "name": "Chuandi Zhang"
    },
    {
      "name": "Jianglong Zhang"
    },
    {
      "name": "Zihang Gao"
    },
    {
      "name": "Ziqi Li"
    },
    {
      "name": "Feiran Shen"
    },
    {
      "name": "Lunhua He"
    },
    {
      "name": "Peijie Sun"
    },
    {
      "name": "Hao Deng"
    },
    {
      "name": "Junsen Xiang"
    },
    {
      "name": "Wentao Jin"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fzwqnn7fw98p1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.28038",
  "fulltext_url": null,
  "id": "fzwqnn7fw98p1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.28038",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.str-el"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2610.28038",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-20",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fzwqnn7fw98p1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:34:04Z",
      "native_id": "2610.28038",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.28038"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Rare-earth tuning of magnetic entropy and interaction scales in K$_3$$Ln$(PO$_4$)$_2$ ($Ln$ = Yb, Gd) for adiabatic demagnetization refrigeration",
  "title_text": "Rare-earth tuning of magnetic entropy and interaction scales in K_3Ln(PO_4)_2 (Ln = Yb, Gd) for adiabatic demagnetization refrigeration",
  "type": "preprint",
  "updated_at": "2026-10-30T12:34:04Z",
  "url": "https://research.draconitic.com/paper/fzwqnn7fw98p1",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/gnh9-srtk",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}