We determine the phase diagram of copper nitrate $\text{Cu}{({\text{NO}}_{3})}_{2}\ifmmode\cdot\else\textperiodcentered\fi{}2.5{\mathrm{D}}_{2}\text{O}$ in the context of quantum phase transitions and novel states of matter. We establish this compound as an ideal candidate to study quasi-1D Luttinger liquids, 3D Bose-Einstein-Condensation of triplons, and the crossover between 1D and 3D physics. Magnetocaloric effect, magnetization, and neutron scattering data provide clear evidence for transitions into a Luttinger liquid regime and a 3D long-range ordered phase as a function of field and temperature. Theoretical simulations of this model material allow us to fully establish the phase diagram and to discuss it in the context of dimerized spin systems.We determine the phase diagram of copper nitrate $\text{Cu}{({\text{NO}}_{3})}_{2}\ifmmode\cdot\else\textperiodcentered\fi{}2.5{\mathrm{D}}_{2}\text{O}$ in the context of quantum phase transitions and novel states of matter. We establish this compound as an ideal candidate to study quasi-1D Luttinger liquids, 3D Bose-Einstein-Condensation of triplons, and the crossover between 1D and 3D physics. Magnetocaloric effect, magnetization, and neutron scattering data provide clear evidence for transitions into a Luttinger liquid regime and a 3D long-range ordered phase as a function of field and temperature. Theoretical simulations of this model material allow us to fully establish the phase diagram and to discuss it in the context of dimerized spin systems.

arXiv:1406.6149Physical Review BFeb 27, 201524 citations

Spinless Luttinger Liquids

WORLD SCIENTIFIC eBooksMar 1, 20080 citations

Absence of a sliding Luttinger liquid phase in the planar pyrochlore

Marcelo Arlego, Wolfram Brenig

Using series expansion based on the flow equation method we study the zero temperature properties of the spin- $1∕2$ planar pyrochlore antiferromagnet in the limit of strong diagonal coupling. Starting from the limit of decoupled crossed dimers we analyze the evolution of the ground state energy and the elementary triplet excitations in terms of two coupling constants describing the inter dimer exchange. In the limit of weakly coupled spin- $1∕2$ chains we find that the fully frustrated inter chain coupling is critical, forcing a dimer phase which adiabatically connects to the state of isolated dimers. This result is consistent with findings by O. Starykh, A. Furusaki, and L. Balents [Phys. Rev. B 72, 094416 (2005)] which is inconsistent with a two-dimensional sliding Luttinger liquid phase at finite inter chain coupling.Using series expansion based on the flow equation method we study the zero temperature properties of the spin-$1∕2$ planar pyrochlore antiferromagnet in the limit of strong diagonal coupling. Starting from the limit of decoupled crossed dimers we analyze the evolution of the ground state energy and the elementary triplet excitations in terms of two coupling constants describing the inter dimer exchange. In the limit of weakly coupled spin-$1∕2$ chains we find that the fully frustrated inter chain coupling is critical, forcing a dimer phase which adiabatically connects to the state of isolated dimers. This result is consistent with findings by O. Starykh, A. Furusaki, and L. Balents [Phys. Rev. B 72, 094416 (2005)] which is inconsistent with a two-dimensional sliding Luttinger liquid phase at finite inter chain coupling.

arXiv:cond-mat/0606074Physical Review BJan 8, 200714 citations

Probing Luttinger Liquids

ScienceMar 31, 20050 citations

Critical properties and Bose-Einstein condensation in dimer spin systems

E. Orignac, R. Citro, Thierry Giamarchi

We analyze the spin relaxation time $1∕{T}_{1}$ for a system made of weakly coupled one-dimensional ladders. This system allows us to probe the dimensional crossover between a Luttinger liquid and a Bose-Einstein condensate of magnons. We obtain the temperature dependence of $1∕{T}_{1}$ in the various dimensional regimes, and discuss the experimental consequences.We analyze the spin relaxation time $1∕{T}_{1}$ for a system made of weakly coupled one-dimensional ladders. This system allows us to probe the dimensional crossover between a Luttinger liquid and a Bose-Einstein condensate of magnons. We obtain the temperature dependence of $1∕{T}_{1}$ in the various dimensional regimes, and discuss the experimental consequences.

arXiv:cond-mat/0701590Physical Review BApr 17, 200739 citations

Using series expansion based on the flow equation method we study the zero temperature properties of the spin-

1∕2

planar pyrochlore antiferromagnet in the limit of strong diagonal coupling. Starting from the limit of decoupled crossed dimers we analyze the evolution of the ground state energy and the elementary triplet excitations in terms of two coupling constants describing the inter dimer exchange. In the limit of weakly coupled spin-

1∕2

chains we find that the fully frustrated inter chain coupling is critical, forcing a dimer phase which adiabatically connects to the state of isolated dimers. This result is consistent with findings by O. Starykh, A. Furusaki, and L. Balents [Phys. Rev. B 72, 094416 (2005)] which is inconsistent with a two-dimensional sliding Luttinger liquid phase at finite inter chain coupling.

We analyze the spin relaxation time

1∕{T}_{1}

for a system made of weakly coupled one-dimensional ladders. This system allows us to probe the dimensional crossover between a Luttinger liquid and a Bose-Einstein condensate of magnons. We obtain the temperature dependence of

1∕{T}_{1}

in the various dimensional regimes, and discuss the experimental consequences.