Drastic Change of Magnetic Phase Diagram in Doped Quantum Antiferromagnet TlCu${}_{1-x}$Mg${}_x$Cl${}_3$

Abstract

TlCuCl${}_3$ is a coupled spin dimer system, which has a singlet ground state with an excitation gap of $\Delta /g{\mu }_{\mathrm{B}}$ = 5.5 T. TlCu${}_{1-x}$Mg${}_x$Cl${}_3$ doped with nonmagnetic Mg${}^{2+}$ ions undergoes impurity-induced magnetic ordering. Because triplet excitation with a finite gap still remains, this doped system can also undergo magnetic-field-induced magnetic ordering. By specific heat measurements and neutron scattering experiments under a magnetic field, we investigated the phase diagram in TlCu${}_{1-x}$Mg${}_x$Cl${}_3$ with $x\sim 0.01$, and found that impurity- and field-induced ordered phases are the same. The gapped spin liquid state observed in pure TlCuCl${}_3$ is completely wiped out by the small amount of doping.

9 pages, 5 figures, jpsj2 class file, to be published in J. Phy. Soc. Jpn. Vol.75 No.3 (2006); layout changed, unrelated figure removed

References in corpus (11)

• Realization of Bose-Einstein condensation of dilute magnons in TlCuCl${}_3$
• Field- and pressure-induced magnetic quantum phase transitions in TlCuCl_3
• Spin-Vacancy-Induced Long-Range Order in a New Haldane-Gap Antiferromagnet
• Observation of Field-Induced Transverse Néel Ordering in the Spin Gap System TlCuCl${}_3$
• Low-Temperature Properties of the Randomly Depleted Heisenberg Ladder
• Impurity-Induced Antiferromagnetic Ordering in the Spin Gap System TlCuCl_3
• Neutron Diffraction Study of the Pressure-Induced Magnetic Ordering in the Spin Gap System TlCuCl${}_3$
• Site-Dilution-Induced Antiferromagnetic Long-Range Order in Two-Dimensional Spin-Gapped Heisenberg Antiferromagnet
• Scaling Properties of Antiferromagnetic Transition in Coupled Spin Ladder Systems Doped with Nonmagnetic Impurities
• Field-induced disorder in a gapped spin system with non-magnetic impurities
• Neutron Scattering Study of Magnetic Ordering and Excitations in the Doped Spin Gap System Tl(Cu${}_{1-x}$Mg${}_x$)Cl${}_3$

Cited by in corpus (6)

• Diluting a triangular-lattice spin liquid: Synthesis and characterization of NaYb${}_{1-x}$Lu${}_x$S${}_2$ single crystals
• Magnetic Bose glass phases of coupled antiferromagnetic dimers with site dilution
• A mean-field theory for strongly disordered non-frustrated antiferromagnets
• Crossover from impurity-induced ordered phase to uniform antiferromagnetic phase under hydrostatic pressure in the doped spin-gap system TlCu${}_{1-x}$Mg${}_x$Cl${}_3$
• Formation of the S=1 paramagnetic centers in the bond-diluted spin-gap magnet
• Pressure-induced new magnetic phase in Tl(Cu${}_{0.985}$Mg${}_{0.015}$)Cl${}_3$ probed by muon spin rotation