title: Novel dynamic ccaling regime in hole-doped La2CuO4.
abstract: Only 3% hole doping by Li is sufficient to suppress the long-range three-dimensional (3D) antiferromagnetic order in La2CuO4. The spin dynamics of such a 2D spin liquid state at T<<J was investigated with measurements of the dynamic magnetic structure factor S(omega,q), using cold neutron spectroscopy, for single crystalline La2Cu0.94Li0.06O4. S(omega,q) peaks sharply at (pi,pi) and crosses over around 50 K from omega/T scaling to a novel low temperature regime characterized by a constant-energy scale. The possible connection to a crossover from the quantum critical to the quantum disordered regime of the 2D antiferromagnetic spin liquid is discussed.
authors.affiliation: Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Bao
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Qiu
authors.forename: J L
authors.initials: JL
authors.lastname: Sarrao