@article{62505fa58a654125834a65653b59b127,
title = "Extended Quantum Critical Phase in a Magnetized Spin-[Formula presented] Antiferromagnetic Chain",
abstract = "Measurements are reported of the magnetic field dependence of excitations in the quantum critical state of the spin [Formula presented] linear chain Heisenberg antiferromagnet copper pyrazine dinitrate (CuPzN). The complete spectrum was measured at [Formula presented] for [Formula presented] and [Formula presented], where the system is [Formula presented] magnetized. At [Formula presented], the results are in agreement with exact calculations of the dynamic spin correlation function for a two-spinon continuum. At [Formula presented], there are multiple overlapping continua with incommensurate soft modes. The boundaries of these continua confirm long-standing predictions, and the intensities are consistent with exact diagonalization and Bethe ansatz calculations.",
author = "Stone, {M. B.} and Reich, {D. H.} and C. Broholm and K. Lefmann and C. Rischel and Landee, {C. P.} and Turnbull, {M. M.}",
year = "2003",
month = jul,
day = "17",
doi = "10.1103/PhysRevLett.91.037205",
language = "English",
volume = "91",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "3",
}