20.500.12556/RUL-177911 Influence of La doping on the magnetic properties of the two-dimensional spin-gapped system SrCu$_2$(BO$_3$)$_2$ Doping of the two-dimensional dimer antiferromagnet SrCu$_2$(BO$_3$)$_2$ has long been proposed as a potential route toward realizing resonating valence bond superconductivity in this system; however, experimental progress has remained limited. This study explores the effects of La doping on the ground state of SrCu$_2$(BO$_3$)$_2$ and reports the first flux growth of Sr$_{1−x}$La$_x$Cu$_2$(BO$_3$)$_2$ single crystals with nominal doping levels up to x = 0.15. Powder X-ray diffraction and energy-dispersive X-ray spectroscopy confirm the successful incorporation of La on the Sr sites within the same tetragonal I$\overline 4$2m structure, although the effective doping was found to be <50% of the nominal concentration. La doping induces systematic changes in the magnetic properties of SrCu$_2$(BO$_3$)$_2$, with a reduction of the effective spin gap from 28.2 K for the undoped sample to 20.3 K for x = 0.15, as determined from the low-temperature magnetic susceptibility. The X-band electron spin resonance measurements reveal the emergence of unpaired Cu$^{2+}$ spins, which develop antiferromagnetic correlations below ∼5.5 K. These findings corroborate the breaking of the local spin dimers in SrCu$_2$(BO$_3$)$_2$ induced by La doping. No superconductivity is observed across the entire doping range studied. antiferromagnets doping crystal structure electron paramagnetic resonance spectroscopy quantum mechanics thermodynamic properties antiferomagneti dopiranje antiferomagnetizem superprevodnost lantan magnetne lastnosti true false true Angleški jezik Slovenski jezik Članek v reviji 2026-01-13 10:00:46 2026-01-13 10:00:47 2026-01-14 04:26:31 0000-00-00 00:00:00 2026 0 0 Str. 291–302 iss. 1 Vol. 65 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.7+621.9 1520-510X 10.1021/acs.inorgchem.5c04249 264142851 influence-of-la-doping-on-the-magnetic-properties-of-the-two-dimensional-spin-gapped-system-srcu2(bo3)2.pdf influence-of-la-doping-on-the-magnetic-properties-of-the-two-dimensional-spin-gapped-system-srcu2(bo3)2.pdf 1 DFAA89AC3088A18572AC464FAB8EF8B8 3486f9e249ac0d91e8caa62aea28a65013b7f463919e64eab2ca8275f2cab142 6d299c8a-f079-11f0-bf92-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=225349 https://pubs.acs.org/doi/10.1021/acs.inorgchem.5c04249 1 52a32bb4-f05e-11f0-bf92-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=225330 Fakulteta za gradbeništvo in geodezijo Fakulteta za matematiko in fiziko 0 0 0