Electronic structure of Ba3CuSb2O9: A candidate quantum spin liquid compound
Апстракт
Using density-functional methods, we study the electronic structure of Ba3CuSb2O9, a candidate material for the quantum spin liquid behavior. We study both the triangular lattice as well as the recently proposed hexagonal lattice structures with flipped Cu-Sb dumbbells. The band structure near the Fermi energy is described very well by a tight-binding Hamiltonian involving the Cu (e(g)) orbitals, confirming their central role in the physics of the problem. A minimal tight-binding Hamiltonian for the triangular structure is presented. The Cu (d(9)) ions (a single e(g) hole in the band structure) present in the compound are expected to be Jahn-Teller centers, while the nature of the Jahn-Teller distortions in this material is still under debate. Solving a simple model by exact diagonalization, we show that electronic correlation effects in general enhance the tendency towards a Jahn-Teller distortion by reducing the kinetic energy due to correlation effects. Our density-functional calcul...ations do indeed show a significant Jahn-Teller distortion of the CuO6 octahedra when we include the correlation effects within the Coulomb-corrected GGA+U method, so that the Jahn-Teller effect is correlation driven. We argue for the presence of a random static Jahn-Teller distortion in the hexagonal structure rather than a dynamical one because of the broken octahedral symmetry around the CuO6 octahedra and the potential fluctuations inherently present in the system caused by a significant disorder, which is believed to be present, in particular, due to the flipped Cu-Sb dumbbells.
Извор:
Physical Review B: Condensed Matter and Materials Physics, 2014, 89, 8Финансирање / пројекти:
- U. S. Department of Energy [DE-FG02-00ER45818]
DOI: 10.1103/PhysRevB.89.085130
ISSN: 2469-9950; 2469-9969
WoS: 000332420500003
Scopus: 2-s2.0-84897729888
Колекције
Институција/група
VinčaTY - JOUR AU - Shanavas, K. V. AU - Popović, Zoran S. AU - Satpathy, Sashi PY - 2014 UR - https://vinar.vin.bg.ac.rs/handle/123456789/5913 AB - Using density-functional methods, we study the electronic structure of Ba3CuSb2O9, a candidate material for the quantum spin liquid behavior. We study both the triangular lattice as well as the recently proposed hexagonal lattice structures with flipped Cu-Sb dumbbells. The band structure near the Fermi energy is described very well by a tight-binding Hamiltonian involving the Cu (e(g)) orbitals, confirming their central role in the physics of the problem. A minimal tight-binding Hamiltonian for the triangular structure is presented. The Cu (d(9)) ions (a single e(g) hole in the band structure) present in the compound are expected to be Jahn-Teller centers, while the nature of the Jahn-Teller distortions in this material is still under debate. Solving a simple model by exact diagonalization, we show that electronic correlation effects in general enhance the tendency towards a Jahn-Teller distortion by reducing the kinetic energy due to correlation effects. Our density-functional calculations do indeed show a significant Jahn-Teller distortion of the CuO6 octahedra when we include the correlation effects within the Coulomb-corrected GGA+U method, so that the Jahn-Teller effect is correlation driven. We argue for the presence of a random static Jahn-Teller distortion in the hexagonal structure rather than a dynamical one because of the broken octahedral symmetry around the CuO6 octahedra and the potential fluctuations inherently present in the system caused by a significant disorder, which is believed to be present, in particular, due to the flipped Cu-Sb dumbbells. T2 - Physical Review B: Condensed Matter and Materials Physics T1 - Electronic structure of Ba3CuSb2O9: A candidate quantum spin liquid compound VL - 89 IS - 8 DO - 10.1103/PhysRevB.89.085130 ER -
@article{ author = "Shanavas, K. V. and Popović, Zoran S. and Satpathy, Sashi", year = "2014", abstract = "Using density-functional methods, we study the electronic structure of Ba3CuSb2O9, a candidate material for the quantum spin liquid behavior. We study both the triangular lattice as well as the recently proposed hexagonal lattice structures with flipped Cu-Sb dumbbells. The band structure near the Fermi energy is described very well by a tight-binding Hamiltonian involving the Cu (e(g)) orbitals, confirming their central role in the physics of the problem. A minimal tight-binding Hamiltonian for the triangular structure is presented. The Cu (d(9)) ions (a single e(g) hole in the band structure) present in the compound are expected to be Jahn-Teller centers, while the nature of the Jahn-Teller distortions in this material is still under debate. Solving a simple model by exact diagonalization, we show that electronic correlation effects in general enhance the tendency towards a Jahn-Teller distortion by reducing the kinetic energy due to correlation effects. Our density-functional calculations do indeed show a significant Jahn-Teller distortion of the CuO6 octahedra when we include the correlation effects within the Coulomb-corrected GGA+U method, so that the Jahn-Teller effect is correlation driven. We argue for the presence of a random static Jahn-Teller distortion in the hexagonal structure rather than a dynamical one because of the broken octahedral symmetry around the CuO6 octahedra and the potential fluctuations inherently present in the system caused by a significant disorder, which is believed to be present, in particular, due to the flipped Cu-Sb dumbbells.", journal = "Physical Review B: Condensed Matter and Materials Physics", title = "Electronic structure of Ba3CuSb2O9: A candidate quantum spin liquid compound", volume = "89", number = "8", doi = "10.1103/PhysRevB.89.085130" }
Shanavas, K. V., Popović, Z. S.,& Satpathy, S.. (2014). Electronic structure of Ba3CuSb2O9: A candidate quantum spin liquid compound. in Physical Review B: Condensed Matter and Materials Physics, 89(8). https://doi.org/10.1103/PhysRevB.89.085130
Shanavas KV, Popović ZS, Satpathy S. Electronic structure of Ba3CuSb2O9: A candidate quantum spin liquid compound. in Physical Review B: Condensed Matter and Materials Physics. 2014;89(8). doi:10.1103/PhysRevB.89.085130 .
Shanavas, K. V., Popović, Zoran S., Satpathy, Sashi, "Electronic structure of Ba3CuSb2O9: A candidate quantum spin liquid compound" in Physical Review B: Condensed Matter and Materials Physics, 89, no. 8 (2014), https://doi.org/10.1103/PhysRevB.89.085130 . .