Coexistence of metallic and nonmetallic properties in the pyrochlore Lu2Rh2O7
Source abstract
Abstract
Abstract Transition metal oxides of the 4d and 5d block have recently become the targets of materials discovery, largely due to their strong spin–orbit coupling that can generate exotic magnetic and electronic states. Here, we report the high-pressure synthesis of Lu2Rh2O7, a new cubic pyrochlore oxide based on 4d5 Rh4+, and characterizations via thermodynamic, electrical transport, and muon spin relaxation measurements. Magnetic susceptibility measurements reveal a large temperature-independent Pauli paramagnetic contribution, while heat capacity shows an enhanced Sommerfeld coefficient, γ = 21.8(1) mJ/mol-Rh K2. Muon spin relaxation measurements confirm that Lu2Rh2O7 remains paramagnetic down to 2 K. Taken in combination, these three measurements suggest that Lu2Rh2O7 is a correlated paramagnetic metal with a Wilson ratio of RW = 2.5. However, electric transport measurements present a striking contradiction as the resistivity of Lu2Rh2O7 is observed to monotonically increase with decreasing temperature, indicative of a nonmetallic state. Furthermore, although the magnitude of the resistivity is that of a semiconductor, the temperature dependence does not obey any conventional form. Thus, we propose that Lu2Rh2O7 may belong to the same novel class of non-Fermi liquids as the nonmetallic metal FeCrAs.
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Research context
OpenAlex topics: Advanced Condensed Matter Physics · Rare-earth and actinide compounds · Magnetic and transport properties of perovskites and related materials
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References (55)
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1. Lee, P. A., Nagaosa, N. & Wen, X.-G. Doping a Mott insulator: physics of high-temperature superconductivity. Rev. Mod. Phys. 78, 17–85 (2006).10.1103/RevModPhys.78.17 ↗
2. Witczak-Krempa, W., Chen, G., Kim, Y. B. & Balents, L. Correlated quantum phenomena inthe strong spin–orbit regime. Annu. Rev. Condens. Matter Phys. 5, 57–82 (2014).10.1146/annurev-conmatphys-020911-125138 ↗
3. Gardner, J. S., Gingras, M. J. P. & Greedan, J. E. Magnetic pyrochlore oxides. Rev. Mod. Phys. 82, 53–107 (2010).10.1103/RevModPhys.82.53 ↗
4. Nakatsuji, S. et al. Metallic spin-liquid behavior of the geometrically frustrated kondo lattice Pr2lr2O7. Phys. Rev. Lett. 96, 087204 (2006).10.1103/PhysRevLett.96.087204 ↗
5. Lacroix, C. Frustrated metallic systems: a review of some peculiar behavior. J. Phys. Soc. Jpn. 79, 011008 (2010).10.1143/JPSJ.79.011008 ↗
6. Julian, S. & Kee, H. Y. Frustrated metallic magnets. Phys. Can. 68, 95–98 (2012).
7. Paddison, J. A. M. et al. Emergent frustration in co-doped β-Mn. Phys. Rev. Lett. 110, 267207 (2013).10.1103/PhysRevLett.110.267207 ↗
8. Billington, D. et al. Magnetic frustration, short-range correlations and the role of the paramagnetic fermi surface of PdCrO2. Sci. Rep. 5, 12428 (2015).10.1038/srep12428 ↗
9. Sapkota, A. et al. Effective one-dimensional coupling in the highly frustrated square-lattice itinerant magnet CaCo2−yAs2. Phys. Rev. Lett. 119, 147201 (2017).10.1103/PhysRevLett.119.147201 ↗
10. Ramirez, A. P. Strongly geometrically frustrated magnets. Annu. Rev. Mater. Sci. 24, 453–480 (1994).10.1146/annurev.ms.24.080194.002321 ↗
11. Subramanian, M. A., Aravamudan, G. & Subba Rao, G. V. Oxide pyrochlores: a review. Prog. Solid State Chem. 15, 55–143 (1983).10.1016/0079-6786(83)90001-8 ↗
12. Wan, X., Turner, A. M., Vishwanath, A. & Savrasov, S. Y. Topological semimetal and Fermi-arcsurface states in the electronic structure of pyrochlore iridates. Phys. Rev. B 83, 205101 (2011).10.1103/PhysRevB.83.205101 ↗
13. Blacklock, K. & White, H. W. Specific heats of the pyrochlore compounds Cd2Re2O7 and Cd2Ru2Oz. J. Chem. Phys. 71, 5287–5289 (1979).10.1063/1.438340 ↗
14. Sakai, H. et al. Superconductivity in a pyrochlore oxide, Cd2Re2O7. J. Phys. Condens. Matter 13, L785–L790 (2001).10.1088/0953-8984/13/33/105 ↗
15. Sleight, A. W., Gillson, J. L., Weiher, J. F. & Bindloss, W. Semiconductor–metal transition in novel Cd2Os2O7. Solid State Commun. 14, 357–359 (1974).10.1016/0038-1098(74)90917-X ↗
16. Mandrus, D. et al. Continuous metal–insulator transition in the pyrochlore Cd2Os2O7. Phys. Rev. B 63, 195104 (2001).10.1103/PhysRevB.63.195104 ↗
17. Calder, S. et al. Spin–orbit-driven magnetic structure and excitation in the 5d pyrochlore Cd2Os2O7. Nat. Commun. 7, 11651 (2016).10.1038/ncomms11651 ↗
18. Sohn, C. H. et al. Strong spin–phonon coupling mediated by single ion anisotropy in the all-in-all-out pyrochlore magnet Cd2Os2O7. Phys. Rev. Lett. 118, 117201 (2017).10.1103/PhysRevLett.118.117201 ↗
19. Sleight, A. W. & Gillson, J. L. Platinum metal pyrochlores of the type Tl2M2O7. Mater. Res. Bull. 6, 781–784 (1971).10.1016/0025-5408(71)90114-0 ↗
20. Lazarev, V. B. & Shaplygin, I. S. Electrical properties of mixed oxides containing a platinum metal and a non-noble metal. Russ. J. Inorg. Chem. 23, 163–170 (1978).
21. Martins, C., Aichhorn, M. & Biermann, S. Coulomb correlations in 4d and 5d oxides from first principles or how spin–orbit materials choose their effective orbital degeneracies. J. Phys. Condens. Matter 29, 263001 (2017).10.1088/1361-648X/aa648f ↗
22. Uematsu, D. et al. Large trigonal-field effect on spin–orbit coupled states in a pyrochlore iridate. Phys. Rev. B 92, 094405 (2015).10.1103/PhysRevB.92.094405 ↗
23. Rau, J. G., Lee, E. K. H. & Kee, H.-Y. Spin–orbit physics giving rise to novel phases in correlated systems: iridates and related materials. Annu. Rev. Condens. Matter Phys. 7, 195–221 (2016).10.1146/annurev-conmatphys-031115-011319 ↗
24. Birol, T. & Haule, K. J eff = 1/2 Mott-insulating state in Rh and Ir fluorides. Phys. Rev. Lett. 114, 096403 (2015).10.1103/PhysRevLett.114.096403 ↗
25. Martins, C., Aichhorn, M., Vaugier, L. & Biermann, S. Reduced effective spin-orbital degeneracy and spin-orbital ordering in paramagnetic transition-metal oxides: Sr2IrO4 versus Sr2RhO4. Phys. Rev. Lett. 107, 266404 (2011).10.1103/PhysRevLett.107.266404 ↗
26. Luo, Y. et al. Li2RhO3: a spin-glassy relativistic Mott insulator. Phys. Rev. B 87, 161121 (2013).10.1103/PhysRevB.87.161121 ↗
27. Wu, W., McCollam, A., Swainson, I., Rancourt, D. G. & Julian, S. R. A novel non-Fermi-liquid state in the iron-pnictide FeCrAs. Europhys. Lett. 85, 17009 (2009).10.1209/0295-5075/85/17009 ↗
28. Akrap, A., Dai, Y. M., Wu, W., Julian, S. R. & Homes, C. C. Optical properties and electronic structure of the nonmetallic metal FeCrAs. Phys. Rev. B 89, 125115 (2014).10.1103/PhysRevB.89.125115 ↗
29. Muller, O. & Roy, R. Formation and stability of the platinum and rhodium oxides at high oxygen pressures and the structures of Pt3O4, β-PtO2 and RhO2. J. Less Common Met. 16, 129–146 (1968).10.1016/0022-5088(68)90070-2 ↗
30. Shannon, R. D. Synthesis and properties of two new members of the rutile family RhO2 and PtO2. Solid State Commun. 6, 139–143 (1968).10.1016/0038-1098(68)90019-7 ↗
31. Bain, G. A. & Berry, J. F. Diamagnetic corrections and Pascal’s constants. J. Chem. Educ. 85, 532–536 (2008).10.1021/ed085p532 ↗
32. Yamaura, K. & Takayama-Muromachi, E. Enhanced paramagnetism of the 4d itinerant electrons in the rhodium oxide perovskite SrRhO3. Phys. Rev. B 64, 224424 (2001).10.1103/PhysRevB.64.224424 ↗
33. Singh, D. J. Prospects for quantum criticality in perovskite SrRhO3. Phys. Rev. B 67, 054507 (2003).10.1103/PhysRevB.67.054507 ↗
34. Saha, S. et al. Temperature-dependent Raman and x-ray studies of the spin-ice pyrochlore Dy2Ti2O7 and nonmagnetic pyrochlore Lu2Ti2O7. Phys. Rev. B 78, 214102 (2008).10.1103/PhysRevB.78.214102 ↗
35. Maczka, M. et al. Temperature-dependent Raman scattering studies of the geometrically frustrated pyrochlores Dy2Ti2O7, Gd2Ti2O7 and Er2Ti2O7. J. Raman Spectrosc. 39, 537–544 (2008).10.1002/jrs.1875 ↗
36. Maeno, Y. et al. Two-dimensional Fermi liquid behavior of the superconductor Sr2RuO4. J. Phys. Soc. Jpn. 66, 1405–1408 (1997).10.1143/JPSJ.66.1405 ↗
37. Park, J. et al. Robust singlet dimers with fragile ordering in two-dimensional honeycomb lattice of Li2RuO3. Sci. Rep. 6, 25238 (2016).10.1038/srep25238 ↗
38. Perry, R. S. et al. Sr2RhO4: a new, clean correlated electron metal. New J. Phys. 8, 175 (2006).10.1088/1367-2630/8/9/175 ↗
39. Stewart, G. R. Heavy-fermion systems. Rev. Mod. Phys. 56, 755–787 (1984).10.1103/RevModPhys.56.755 ↗
40. Shiga, M., Fujisawa, K. & Wada, H. Spin liquid behavior of highly frustrated Y(Sc)Mn2 and effects of nonmagnetic impurity. J. Phys. Soc. Jpn. 62, 1329–1336 (1993).10.1143/JPSJ.62.1329 ↗
41. Kondo, S. et al. LiV2O4: a heavy fermion transition metal oxide. Phys. Rev. Lett. 78, 372–373 (1997).10.1103/PhysRevLett.78.3729 ↗
42. Lacroix, C. Heavy-fermion behavior of itinerant frustrated systems: β-Mn, Y(Sc)Mn2, and LiV2O4. Can. J. Phys. 79, 1469–1473 (2001).10.1139/p01-112 ↗
43. Wada, H. et al. Spin fluctuations of Y(Mn1−xAlx)2 and Y1−xScxMn2. J. Magn. Magn. Mater. 70, 17–19 (1987).10.1016/0304-8853(87)90350-7 ↗
44. Palstra, T. T. M. et al. Superconducting and magnetic transitions in the heavy-fermion system URu2Si2. Phys. Rev. Lett. 55, 2727–2730 (1985).10.1103/PhysRevLett.55.2727 ↗
45. Frings, P. H., Franse, J. J. M., De Boer, F. R. & Menovsky, A. Magnetic properties of UxPty compounds. J. Magn. Magn. Mater. 31, 240–242 (1983).10.1016/0304-8853(83)90232-9 ↗
46. Zhou, J.-S., Goodenough, J. B. & Dabrowski, B. Transition from Curie–Weiss to enhanced Pauli paramagnetism in RNiO3 (R = La, Pr, Gd). Phys. Rev. B 67, 020404 (2003).10.1103/PhysRevB.67.020404 ↗
47. Yamaura, K., Huang, Q., Young, D. P., Noguchi, Y. & Takayama-Muromachi, E. Crystal structure and electronic and magnetic properties of the bilayered rhodium oxide Sr3Rh2O7. Phys. Rev. B 66, 134431 (2002).10.1103/PhysRevB.66.134431 ↗
48. Yamaura, K., Huang, Q., Young, D. P. & Takayama-Muromachi, E. Crystal structure and magnetic properties of the trilayered perovskite Sr4Rh3O10: a new member of the strontium rhodate family. Chem. Mater. 16, 3424–3430 (2004).10.1021/cm0491072 ↗
49. Yamaura, K. et al. High-pressure synthesis, crystal structure determination, and a Ca substitution study of the metallic rhodium oxide NaRh2O4. Chem. Mater. 17, 359–365 (2005).10.1021/cm0483846 ↗
50. Yamaura, K. & Takayama-Muromachi, E. High-pressure synthesis of the perovskite rhodate CaRhO3. Phys. C 445, 54–56 (2006).10.1016/j.physc.2006.03.076 ↗
51. Rau, J. G. & Kee, H.-Y. Hidden spin liquid in an antiferromagnet: applications to FeCrAs. Phys. Rev. B 84, 104448 (2011).10.1103/PhysRevB.84.104448 ↗
52. Nevidomskyy, A. H. & Coleman, P. Kondo resonance narrowing in d- and f-electron systems. Phys. Rev. Lett. 103, 147205 (2009).10.1103/PhysRevLett.103.147205 ↗
53. Georges, A., de’Medici, L. & Mravlje, J. Strong correlations from Hunds coupling. Annu. Rev. Condens. Matter Phys. 4, 137–178 (2013).10.1146/annurev-conmatphys-020911-125045 ↗
54. Plumb, K. W. et al. From mean-field localized magnetism to itinerant spin fluctuations in the nonmetallic metal FeCrAs. Phys. Rev. B 97, 184431 (2018).10.1103/PhysRevB.97.184431 ↗
55. Rodriguez-Carvajal, J. Recent advances in magnetic structure determination by neutron powder diffraction. Phys. B Condens. Matter 192, 55–69 (1993).10.1016/0921-4526(93)90108-I ↗