Work

Dominant Kitaev interaction and field-induced quantum phase transitions in triangular-lattice KCeSe 2

Year: 2025

Type: article

Abstract: Realizing Kitaev interactions on triangular lattices offers a compelling platform for exploring quantum spin liquid physics beyond the conventional honeycomb-lattice framework. Here, we investigate the triangular-lattice antiferromagnet KCeSe 2 , where multiple probes reveal strong magnetic anisotropy, suggesting significant Kitaev physics. Through detailed and combined analysis of magnetization, neutron scattering, and thermodynamic experiments, we identify dominant ferromagnetic Kitaev ( K = − 1.82 K ) and antiferromagnetic Heisenberg ( J = 1.34 K ) interactions that stabilize a stripe- y z ordered ground state via an order-by-disorder mechanism. Magnetic fields applied along the Kitaev bond direction induce two phase transitions at 1.67 and 3.8 T, consistent with density matrix renormalization group calculation predictions of a progression from stripe- y z to stripe-canted and spin-polarized phases. Near the 1.67 T quantum critical point, enhanced quantum fluctuations suggest conditions favorable for exotic excitations. These results establish KCeSe 2 as a platform for exploring Kitaev physics on triangular lattices.

Source: Physical Review Research

DOI: 10.1103/physrevresearch.7.023198