Abstract
The phase diagram in temperature and magnetic field of the metal-organic, two-leg, spin-ladder compound is studied by measurements of the specific heat and the magnetocaloric effect. We demonstrate the presence of an extended spin Luttinger-liquid phase between two field-induced quantum critical points and over a broad range of temperature. Based on an ideal spin-ladder Hamiltonian, comprehensive numerical modeling of the ladder specific heat yields excellent quantitative agreement with the experimental data across the entire phase diagram.
- Received 19 August 2008
DOI:https://doi.org/10.1103/PhysRevLett.101.247202
©2008 American Physical Society