$\mu$SR Study of the Dipole-Octupole Quantum Spin Ice Candidate Ce${}_2$Zr${}_2$O${}_7$

Abstract

The Ce${}^{3+}$ pseudospin-1/2 degrees of freedom in Ce${}_2$Zr${}_2$O${}_7$ possess both dipolar and octupolar character which enables the possibility of novel quantum spin liquid ground states in this material. Here we report new muon spin relaxation and rotation ($\mu$SR) measurements on single crystal samples of Ce${}_2$Zr${}_2$O${}_7$ in zero magnetic field and in magnetic fields directed along the $[1,\bar{1},0]$ and $[1,1,1]$ crystallographic directions, and for magnetic fields directed both longitudinal and transverse to the direction of muon polarization. Our zero-field results show no signs of magnetic ordering or spin freezing, consistent with earlier zero-field $\mu$SR measurements on a powder sample of Ce${}_2$Zr${}_2$O${}_7$, and also with the expectations for a quantum spin ice. However, we measure a more gentle relaxation rate for Ce${}_2$Zr${}_2$O${}_7$ in zero-field at low temperatures than was previously reported. This difference in relaxation rate is likely due to the low oxidation, and correspondingly, the high stoichiometry of our single crystal samples. Longitudinal field measurements confirm that the magnetic dipole moments in Ce${}_2$Zr${}_2$O${}_7$ remain dynamic at $T=0.1$ $\mathrm{K}$. For both $[1,\bar{1},0]$ and $[1,1,1]$ magnetic fields, our $\mu$SR Knight shift measurements show a field-induced leveling off of the magnetic susceptibility at low temperature which is qualitatively consistent with corresponding calculations using the numerical-linked-cluster method in combination with recent estimates for the nearest-neighbour exchange parameters of Ce${}_2$Zr${}_2$O${}_7$.

References in corpus (16)

• Dirac Strings and Magnetic Monopoles in Spin Ice Dy2Ti2O7
• Theory of the [111] magnetization plateau in spin ice
• Unusual liquid state of hard-core bosons on the pyrochlore lattice
• Quantum Spin Ice Dynamics in the Dipole-Octupole Pyrochlore Magnet Ce${}_2$Zr${}_2$O${}_7$
• Is the Yb2Ti2O7 pyrochlore a quantum spin ice?
• A Short Introduction to Numerical Linked-Cluster Expansions
• Pinch Points and Kasteleyn Transitions: How Spin Ice Changes its Entropy
• Magnetization process of spin ice in a [111] magnetic field
• Kagomé ice state in the dipolar spin ice Dy_{2}Ti_{2}O_{7}
• Symmetry Enriched U(1) Topological Orders for Dipole-Octupole Doublets on a Pyrochlore Lattice
• First order metamagnetic transition in Ho2Ti2O7 observed by vibrating coil magnetometry at milli-Kelvin temperatures
• Magnetic field effects in an octupolar quantum spin liquid candidate
• Spin dynamics of the ordered dipolar-octupolar pseudospin-${}^1{/}_2$ pyrochlore Nd${}_2$Zr${}_2$O${}_7$ probed by muon spin relaxation
• Crystal-field states and defect levels in candidate quantum spin ice Ce${}_2$Hf${}_2$O${}_7$
• Thermodynamics of two-dimensional spin models with bimodal random-bond disorder
• Spin correlation in kagomé ice state: neutron scattering study of the dipolar spin ice Dy_{2}Ti_{2}O_{7} under magnetic field along [111]

Cited by in corpus (1)

• Finite Temperature Dynamics in 0-Flux and $\pi$-Flux Quantum Spin Ice: Self-Consistent Exclusive Boson Approach