The pyrochlore Ho2Ti2O7: Synthesis, crystal growth and stoichiometry

Abstract

We have investigated the effect of synthesis and growth conditions on the magnetic, structural, and compositional properties of pyrochlore oxide holmium titanate and demonstrate a method for growing high quality stoichiometric single crystals. A series of polycrystalline samples with various contents of Ti (-0.08 \leqslant x \leqslant 0.08, and nominal compositions of Ho2Ti2+xO7) were synthesized at different temperatures, and characterized using powder X-ray diffraction. The results show that synthesizing powders at a higher temperature of 1500 °C yield single phase compounds. Ti deficient powders showed an increase of lattice constant due to stuffing (Ho into Ti positions), while Ti rich powders showed a decrease in lattice constant due to anti-stuffing (Ti into Ho positions). A post annealing in O2 was found to be necessary to accomplish the anti-stuffing process. Use of the conventional floating zone (FZ) technique introduced Ti deficiency, stuffing, and oxygen vacancies in the grown crystal. Growth of high structural quality and stoichiometric single crystals of Ho2Ti2O7 by the traveling solvent floating zone (TSFZ) is reported. AC susceptibility measurements revealed that the stoichiometric crystal shows a higher ice freezing temperature, indicating that crystal quality and stoichiometry play a key role on low temperature spin ice properties of this compound.

arXiv comment6 figures, 3 tables

References in corpus (13)

• Spin Ice State in Frustrated Magnetic Pyrochlore Materials
• Magnetic Pyrochlore Oxides
• Colloquium: Artificial spin ice: Designing and imaging magnetic frustration
• Zero Point Entropy in Stuffed Spin Ice
• Noisy pulses enhance temporal resolution in pump-probe spectroscopy
• Vacancy defects and monopole dynamics in oxygen-deficient pyrochlores
• Impact of Stoichiometry of Yb2Ti2O7 on its Physical Properties
• Dynamics of the Magnetic Susceptibility Deep in the Coulomb Phase of the Dipolar Spin Ice Material Ho2Ti2O7
• Single crystal growth of the pyrochlores $R_2$Ti${}_2$O${}_7$ ($R$ = rare earth) by the optical floating-zone method
• Reentrant Phase Diagram of $\mathrm{Y}{\mathrm{b}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$ in $⟨111⟩$ Magnetic Field
• Statics and dynamics of the highly correlated spin ice Ho2Ge2O7
• Single crystal growth by the traveling solvent technique: A review
• First order metamagnetic transition in Ho2Ti2O7 observed by vibrating coil magnetometry at milli-Kelvin temperatures

Cited by in corpus (8)

• The Chemistry of Quantum Spin Liquids
• Dipolar spin ice regime proximate to an all-in-all-out Néel ground state in the dipolar-octupolar pyrochlore Ce${}_2$Sn${}_2$O${}_7$
• Monopolar and dipolar relaxation in spin ice Ho${}_2$Ti${}_2$O${}_7$
• Beyond magnons in Nd2ScNbO7: An Ising pyrochlore antiferromagnet with all in all out order and random fields
• Evaluating the Effects of Structural Disorder on the Magnetic Properties of Nd${}_2$Zr${}_2$O${}_7$
• Effects of uniaxial pressure on the spin ice Ho2Ti2O7
• Screening and the Pinch Point Paradox in Spin Ice
• Quantum paramagnetism in a non-Kramers rare-earth oxide: Monoclinic $\mathrm{P}{\mathrm{r}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$