Resetting the Discussion of Exotic Quantum Spin Liquid (QSL) Candidate

April 26, 2024
a) Phase diagram of the Ce-based pyrochlores has a large phase space hosting exotic QSL phases with both magnetic dipolar (top right, traditional 2-pole, North/South, magnetic moment) and octupolar (top left, exotic 8-pole magnetic moment) character. Ce2Sn2O7 hosts a dipolar ordered All-In-All-Out (AIAO) phase, in serious contrast to previous work. b) The position-sensitive detectors of WAND2 provide clear evidence of diffuse neutron scattering features at low wavevector, reminiscent of a dipolar spin-ice, rather than at high wavevector expected for octupolar scattering.

Scientific Achievement

Diffuse neutron diffraction reveals Ce2Sn2O7 does not host octupolar QSL phase, but instead a dipolar ordered phase.

Significance and Impact

Understanding of the extremely sensitive ground state will help researchers tune materials toward desired more exotic states.

Research Details

  • High purity samples grown using hydrothermal techniques. 
  • Powder neutron diffraction (PND) on POWDER and WAND2 uncovered diffuse dipolar spin-ice behavior.
  • Numerical techniques combined heat capacity, magnetization, and PND data to develop a microscopic understanding and determine the appropriate ground state of Ce2Sn2O7.

Dipolar Spin Ice Regime Proximate to an All-In-All-Out Néel Ground State in the Dipolar-Octupolar Pyrochlore Ce2Sn2O
Phys. Rev. X 14, 011005 (2024).