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arXiv · 2511.15678

Intrinsic quantum disorder in Yb2Ti2O7 and the quantum S=1/2 pyrochlore phase diagram

Shang-Shun Zhang·Anish Bhardwaj·S. M. Koohpayeh·D. M. Pajerowski·Jeffrey G. Rau·Hitesh J. Changlani·Allen Scheie
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Abstract

We present an experimental and theoretical study of the anisotropic pyrochlore phase diagram. Inelastic field-dependent neutron scattering on Yb$_2$Ti$_2$O$_7$ shows intrinsic broadening and a flat low-energy magnon mode which is partially captured by interacting magnon models. Exact diagonalization reveals the existence of an emergent quantum phase between ferromagnetism and antiferromagnetism, in which Yb$_2$Ti$_2$O$_7$ Hamiltonian potentially resides. This behavior matches the phenomenology of quantum criticality in heavy fermion systems, and shows Yb$_2$Ti$_2$O$_7$ is a clean system which can be field-tuned from well-defined magnons to a nontrivial quantum ground state. This suggests that quantum criticality is a generic feature of the dipolar phase diagram.

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Shang-Shun Zhang, Anish Bhardwaj, S. M. Koohpayeh, D. M. Pajerowski, Jeffrey G. Rau, Hitesh J. Changlani, Allen Scheie. 2025-11-19. Intrinsic quantum disorder in Yb2Ti2O7 and the quantum S=1/2 pyrochlore phase diagram. https://arxiv.org/abs/2511.15678

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