Higher-magnesium-doping effects on the singlet ground state of the Shastry–Sutherland SrCu$_2$(BO$_3$)$_2$

Šibav, Lia (avtor), Gosar, Žiga (avtor), Knaflič, Tilen (avtor), Jagličić, Zvonko (avtor), King, Graham (avtor), Nojiri, Hiroyuki (avtor), Arčon, Denis (avtor), Dragomir, Mirela (avtor)

Doping of quantum antiferromagnets is an established approach to investigate the robustness of their ground state against the competing phases. Predictions of doping effects on the ground state of the Shastry−Sutherland dimer model are here verified experimentally on Mg-doped SrCu$_2$(BO$_3$)$_2$. A partial incorporation of Mg$^{2+}$ on the Cu$^{2+}$ site in the SrCu$_2$(BO$_3$)$_2$ structure leads to a subtle but systematic lattice expansion with the increasing Mg-doping concentration, which is accompanied by a slight decrease in the spin gap, the Curie−Weiss temperature, and the peak temperature of the susceptibility. These findings indicate a doping-induced breaking of Cu$^{2+}$ spin-1/2 dimers that is also corroborated by X-band EPR spectroscopy that points to a systematic increase in the intensity of free Cu$^{2+}$ sites with increasing Mg-doping concentration. Extending the Mg-doping up to nominal x = 0.10 yielding SrCu$_{1.9}$Mg$_{0.1}$(BO$_3$)$_2$, in the magnetization measurements taken up to 35 T, a suppression of the pseudo-1/8 plateau is found along with a clear presence of an anomaly at an onset critical field μ$_0$H’$_{C0}$ ≈ 9 T. The latter, absent in pure SrCu$_2$(BO$_3$)$_2$, emerges due to the pairwise coupling of liberated Cu$^{2+}$ spin-1/2 entities in the vicinity of Mg-doping induced impurities.

• Jezik: Angleški jezik
• Ključne besede: doping, electron paramagnetic resonance spectroscopy, impurities, magnetic properties, quantum mechanics
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FMF - Fakulteta za matematiko in fiziko ; FGG - Fakulteta za gradbeništvo in geodezijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2024
• Št. strani: Str. 20335–20346
• Številčenje: Vol. 63, iss. 43
• PID: 20.500.12556/RUL-164598
• UDK: 546
• ISSN pri članku: 1520-510X
• DOI: 10.1021/acs.inorgchem.4c02398
• COBISS.SI-ID: 212029955
• Datum objave v RUL: 05.11.2024

Gradivo je del revije

• Naslov: Inorganic chemistry
• Skrajšan naslov: Inorg. chem.
• Založnik: American Chemical Society
• ISSN: 1520-510X
• COBISS.SI-ID: 512805401

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: dopiranje, magnetne lastnosti, spektroskopija, relativistična mehanika