@article{15d2390bfd7e4f00a0759d8a142b4924,
title = "Block Magnetic Excitations in the Orbitally Selective Mott Insulator BaFe 2 Se 3",
abstract = "Iron pnictides and selenides display a variety of unusual magnetic phases originating from the interplay between electronic, orbital, and lattice degrees of freedom. Using powder inelastic neutron scattering on the two-leg ladder BaFe 2 Se 3, we fully characterize the static and dynamic spin correlations associated with the Fe 4 block state, an exotic magnetic ground state observed in this low-dimensional magnet and in Rb 0.89 Fe 1.58 Se 2. All the magnetic excitations of the Fe 4 block state predicted by an effective Heisenberg model with localized spins are observed below 300 meV and quantitatively reproduced. However, the data only account for 16 (3) μ B 2 per Fe 2 +, approximatively 2 / 3 of the total spectral weight expected for localized S = 2 moments. Our results highlight how orbital degrees of freedom in iron-based magnets can conspire to stabilize an exotic magnetic state.",
author = "M. Mourigal and Shan Wu and Stone, {M. B.} and Neilson, {J. R.} and Caron, {J. M.} and McQueen, {T. M.} and Broholm, {C. L.}",
note = "Publisher Copyright: {\textcopyright} 2015 American Physical Society.",
year = "2015",
month = jul,
day = "23",
doi = "10.1103/PhysRevLett.115.047401",
language = "English",
volume = "115",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "4",
}