170 citations · 568 across the 10 of their papers we have counts for
8 papers · 1 filter
Fermionic spin liquid analysis of the paramagnetic state in Volborthite
Li Ern Chern, Robert Schaffer, Sopheak Sorn +1
Recently, thermal Hall effect has been observed in the paramagnetic state of Volborthite, which consists of distorted Kagome layers with local moments. Despite the appearan…
Quantum Spin Liquid in a Breathing Kagome Lattice
Robert Schaffer, Yejin Huh, Kyusung Hwang +1
Motivated by recent experiments on the vanadium oxyfluoride material DQVOF, we examine possible spin liquid phases on a breathing kagome lattice of S=1/2 spins. By performing a pro…
Recent progress on correlated electron systems with strong spin-orbit coupling
Robert Schaffer, Eric Kin-Ho Lee, Bohm-Jung Yang +1
Emergence of novel quantum ground states in correlated electron systems with strong spin-orbit coupling has been a recent subject of intensive studies. While it has been realized t…
Topological spinon semimetals and gapless boundary states in three dimensions
Robert Schaffer, Eric Kin-Ho Lee, Yuan-Ming Lu +1
Recently there has been much effort in understanding topological phases of matter with gapless bulk excitations, which are characterized by topological invariants and protected int…
Heisenberg-Kitaev model on hyperhoneycomb lattice
Eric Kin-Ho Lee, Robert Schaffer, Subhro Bhattacharjee +1
Motivated by recent experiments on LiIrO, we study the phase diagram of the Heisenberg-Kitaev model on a three dimensional lattice of tri-coordinated Ir, dubbed…
Spin-orbital liquids in non-Kramers magnet on Kagome lattice
Robert Schaffer, Subhro Bhattacharjee, Yong Baek Kim
Localized magnetic moments with crystal-field doublet or pseudo-spin 1/2 may arise in correlated insulators with even number of electrons and strong spin-orbit coupling. Such a non…
Quantum Phase Transition in Heisenberg-Kitaev Model
Robert Schaffer, Subhro Bhattacharjee, Yong Baek Kim
We explore the nature of the quantum phase transition between a magnetically ordered state with collinear spin pattern and a gapless spin liquid in the Heisenberg-Kitaev mode…
Superfluid and supersolid phases of lattice bosons with ring-exchange interaction
Robert Schaffer, Anton A. Burkov, Roger G. Melko
We examine the superfluid phase of a hard-core boson model with nearest-neighbor exchange J and four-particle ring-exchange K at half-filling on the square lattice. At zero tempera…