Magnetic order, magnetic correlations and spin dynamics in the pyrochlore antiferromagnet Er2Ti2O7

Abstract

Er2Ti2O7 is believed to be a realization of an XY antiferromagnet on a frustrated lattice of corner-sharing regular tetrahedra. It is presented as an example of the order-by-disorder mechanism in which fluctuations lift the degeneracy of the ground state, leading to an ordered state. Here we report detailed measurements of the low temperature magnetic properties of Er2Ti2O7, which displays a second-order phase transition at T_N \simeq 1.2 K with coexisting short- and long-range orders. Magnetic-susceptibility studies show that there is no spin-glass-like irreversible effect. Heat-capacity measurements reveal that the paramagnetic critical exponent is typical of a 3-dimensional XY magnet while the low-temperature specific heat sets an upper limit on the possible spin-gap value and provides an estimate for the spin-wave velocity. Muon spin relaxation measurements show the presence of spin dynamics in the nanosecond time scale down to 21 mK. This time range is intermediate between the shorter time characterizing the spin dynamics in Tb2Sn2O7, which also displays long- and short-range magnetic order, and the time scale typical of conventional magnets. Hence the ground state is characterized by exotic spin dynamics. We determine the parameters of a symmetry-dictated Hamiltonian restricted to the spins in a tetrahedron, by fitting the paramagnetic diffuse neutron scattering intensity for two reciprocal lattice planes. These data are recorded in a temperature region where the assumption that the correlations are limited to nearest neighbors is fair.

16 pages, 16 figures

References in corpus (34)

• Magnetic Pyrochlore Oxides
• Emergent excitations in a geometrically frustrated magnet
• Quantum Excitations in Quantum Spin Ice
• Coulombic Quantum Liquids in Spin-1/2 Pyrochlores
• Dynamically-Induced Frustration as a Route to a Quantum Spin Ice State in Tb2Ti2O7 via Virtual Crystal Field Excitations and Quantum Many-Body Effects
• Ising pyrochlore magnets: Low temperature properties, ice rules and beyond
• Er2Ti2O7: Evidence of Order by Disorder in a Frustrated Antiferromagnet
• Higgs transition from a magnetic Coulomb liquid to a ferromagnet in Yb_2Ti_2O_7
• First Order Transition in the Spin Dynamics of Geometrically Frustrated Yb2Ti2O7
• Quantum fluctuations in the effective pseudospin-1/2 model for magnetic pyrochlore oxides
• Quantum Melting of Spin Ice: Emergent Cooperative Quadrupole and Chirality
• Magnetic order and spin fluctuations in the spin liquid Tb$\_2$Sn$\_2$O$\_7$
• Quantum order by disorder and accidental soft mode Er2Ti2O7
• Order in the Heisenberg Pyrochlore: The Magnetic Structure of Gd2Ti2O7
• Dy2Ti2O7 Spin Ice: a Test Case for Emergent Clusters in a Frustrated Magnet
• Anomalous Excitation Spectra of Frustrated Quantum Antiferromagnets
• Rods of Neutron Scattering Intensity in Yb2Ti2O7: Compelling Evidence for Significant Anisotropic Exchange in a Magnetic Pyrochlore Oxide
• Structural distortion and the spin liquid state in Tb2Ti2O7
• Magnon Decay in Noncollinear Quantum Antiferromagnets
• Magnetic ordering in Gd2Sn2O7: the archetypal Heisenberg pyrochlore antiferromagnet
• Flat spin wave dispersion in a triangular antiferromagnet
• Spin dynamics and magnetic order in magnetically frustrated Tb2Sn2O7
• Spin Waves and Quantum Criticality in the Frustrated XY Pyrochlore Antiferromagnet Er2Ti2O7
• Magnetic density of states at low energy in geometrically frustrated systems
• Absent pinch points and emergent clusters: further neighbour interactions in the pyrochlore Heisenberg antiferromagnet
• Energetic selection of ordered states in a model of the Er2Ti2O7 frustrated pyrochlore XY antiferromagnet
• Quantum spin configurations in Tb2Ti2O7
• Effective nuclear temperature in a fluctuating spin system
• Effective quantum pseudospin-1/2 model for Yb pyrochlore oxides
• Soft modes in the easy plane pyrochlore antiferromagnet
• Magnetic excitations in the XY-pyrochlore antiferromagnet Er${}_2$Ti${}_2$O${}_7$
• Field evolution of the magnetic structures in Er${}_2$Ti${}_2$O${}_7$ through the critical point
• The magnetic structure of Gd_2Ti_2O_7
• The Magnetic Structure of $E{r}_{2}T{i}_2{O}_7$

Cited by in corpus (39)

• Quantum Spin Ice: A Search for Gapless Quantum Spin Liquids in Pyrochlore Magnets
• Frustrated quantum rare-earth pyrochlores
• Theory of multiple--phase competition in pyrochlore magnets with anisotropic exchange, with application to Yb2Ti2O7, Er2Ti2O7 and Er2Sn2O7
• Living on the edge : ground-state selection in quantum spin-ice pyrochlores
• Experimental Insights into Ground State Selection of Quantum XY Pyrochlores
• Observation of long range magnetic ordering in pyrohafnate Nd2Hf2O7: A neutron diffraction study
• Order by Disorder Spin Wave Gap in the XY Pyrochlore Magnet Er2Ti2O7
• Ground State Phase Diagram of Generic XY Pyrochlore Magnets with Quantum Fluctuations
• Single crystal growth of the pyrochlores $R_2$Ti${}_2$O${}_7$ ($R$ = rare earth) by the optical floating-zone method
• Nd2Sn2O7: an all-in-all-out pyrochlore magnet with no divergence-free field and anomalously slow paramagnetic spin dynamics
• Thermodynamic properties of the Yb2Ti2O7 pyrochlore as a function of temperature and magnetic field: validation of a quantum spin ice exchange Hamiltonian
• Phase Transition and Thermal Order-by-Disorder in the Pyrochlore Quantum Antiferromagnet Er2Ti2O7: a High-Temperature Series Expansion Study
• Order-by-Disorder in the XY Pyrochlore Antiferromagnet Revisited
• Ground state selection in XY pyrochlore antiferromagnets R${}_2$Ge${}_2$O${}_7$ (R = Er, Yb)
• Order by Disorder and Energetic Selection of the Ground State in the XY Pyrochlore Antiferromagnet Er2Ti2O7. An Inelastic Neutron Scattering Study
• Nature of finite-temperature transition in anisotropic pyrochlore Er2Ti2O7
• Order from structural disorder in $XY$ pyrochlore antiferromagnet $\mathrm{E}{\mathrm{r}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$
• XY Antiferromagnetic Ground State in the Effective S=1/2 Pyrochlore Yb2Ge2O7
• Order-by-disorder near criticality in $XY$ pyrochlore magnets
• Evidence for unidimensional low-energy excitations as the origin of persistent spin dynamics in geometrically frustrated magnets
• Phase Competition in the Palmer-Chalker XY Pyrochlore Er${}_2$Pt${}_2$O${}_7$
• Magnetisation process in Er2Ti2O7 and Tb2Ti2O7 at very low temperature
• Muon spin relaxation and inelastic neutron scattering investigations of all-in/all-out antiferromagnet Nd2Hf2O7
• Stripe antiferromagnetic ground state of ideal triangular lattice KErSe${}_2$
• Long-range dynamical magnetic order and spin tunneling in the cooperative paramagnetic states of the pyrochlore analogous spinel antiferromagnets CdYb2X4 (X = S, Se)
• Frustrated magnetism in the Heisenberg pyrochlore antiferromagnets $A$Yb${}_2$$X$${}_4$ ($A$ = Cd, Mg, $X$ = S, Se)
• Magnetic dilution and domain selection in the XY pyrochlore antiferromagnet Er${}_2$Ti${}_2$O${}_7$
• Low-temperature heat transport of the geometrically frustrated antiferromagnets R_2Ti_2O_7 (R = Gd and Er)
• Anomalously slow spin dynamics and short-range correlations in the quantum spin ice systems Yb2Ti2O7 and Yb2Sn2O7
• Field induced phase diagram of the XY pyrochlore antiferromagnet Er${}_2$Ti${}_2$O${}_7$
• Amorphous ferromagnetism and re-entrant magnetic glassiness in Sm${}_2$Mo${}_2$O${}_7$: new insights into the electronic phase diagram of pyrochlore molybdates
• Doping-induced quantum cross-over in Er${}_2$Ti${}_{2-x}$Sn${}_x$O${}_7$
• Holographic antiferromganetic quantum criticality and AdS${}_2$ scaling limit
• Muon diffusion and electronic magnetism in Y${}_2$Ti${}_2$O${}_7$
• Low temperature crystal structure and local magnetometry for the geometrically frustrated pyrochlore Tb2Ti2O7
• Absence of long-range order in an $XY$ pyrochlore antiferromagnet Er${}_2$AlSbO${}_7$
• Effective spin-1/2 exchange interactions in Tb${}_2$Ti${}_2$O${}_7$
• Magnetic order, spin waves and fluctuations in the triangular antiferromagnet La2Ca2MnO7
• Crossover from one- to three-dimensional behavior in the S = 1/2 Heisenberg antiferromagnet Cu(N2H5)2(SO4)2