Related papers: Planar parallel phonon Hall effect and local symme…
Kitaev materials are a promising platform for the realization of quantum spin liquid states. The thermal Hall effect has emerged as a potential probe of exotic excitations within such states. In the Kitaev candidate material…
A surprising "planar" thermal Hall effect, whereby the field is parallel to the current, has recently been observed in a few magnetic insulators, and this has been attributed to exotic excitations such as Majorana fermions or chiral…
Phonons are known to generate a thermal Hall effect in certain insulators, including oxides with rare-earth impurities, quantum paraelectrics, multiferroic materials and cuprate Mott insulators. In each case, a special feature of the…
It has recently become clear that phonons generate a sizable thermal Hall effect in cuprates, whether they are undoped, electron-doped or hole-doped (inside the pseudogap phase). At higher doping, where cuprates are reasonably good metals,…
We report an investigation of the phonon thermal Hall effect in single crystal samples of Y$_2$Ti$_2$O$_7$, Dy$_2$Ti$_2$O$_7$, and DyYTi$_2$O$_7$. We measured the field-linear thermal Hall effect in all three samples. The temperature…
The thermal Hall effect, which arises when heat flows transverse to an applied thermal gradient, has become an important observable in the study of quantum materials. Recent experiments found a large thermal Hall conductivity $\kappa_{xy}$…
In this letter, we report the gigantic thermal Hall effect $\kappa_{xy}$ in the low-field correlated-paramagnetic state of the frustrated pyrochlore Yb$_2$Ti$_2$O$_7$. We observed a record magnitude for the thermal Hall angle in an…
It has become common knowledge that phonons can generate thermal Hall effect in a wide variety of materials, although the underlying mechanism is still controversial. We study longitudinal $\kappa_{xx}$ and transverse $\kappa_{xy}$ thermal…
The phonon Hall effect has been observed in the paramagnetic insulator, Tb3Gd5O12. A magnetic field applied perpendicularly to a heat current induces a temperature gradient that is perpendicular to both the field and the current. We show…
The nature of the pseudogap phase of cuprates remains a major puzzle. One of its new signatures is a large negative thermal Hall conductivity $\kappa_{\rm xy}$, which appears for dopings $p$ below the pseudogap critical doping $p^*$, but…
We investigate the thermal Hall effect in a Kitaev-Heisenberg system, a model for Kitaev candidate $\alpha$-RuCl$_3$, in the presence of the coupling between spin and phonon arising from chlorine atoms' vibration. We observe that the…
It has been known for more than a decade that phonons can produce an off-diagonal thermal conductivity in presence of magnetic field. Recent studies of thermal Hall conductivity, $\kappa_{xy}$, in a variety of contexts, however, have…
With an increasing number of experiments observing phonon thermal Hall effect in magnets, it is theoretically desired to have a minimal model for the phonon thermal Hall effect. In this work, we study a simple model of acoustic phonons and…
Measurements of the thermal Hall conductivity in hole-doped cuprates have shown that phonons acquire chirality in a magnetic field, both in the pseudogap phase and in the Mott insulator state. The microscopic mechanism at play is still…
In a growing number of materials, phonons have been found to generate a thermal Hall effect, but the underlying mechanism remains unclear. Inspired by previous studies that revealed the importance of Tb$^{3+}$ ions in generating the thermal…
It has been known for decades that a magnetic field can deflect phonons as they flow in response to a thermal gradient, producing a thermal Hall effect. Several recent experiments have revealed ratios of the phonon Hall conductivity to the…
The material $\alpha$-RuCl$_3$ has been the subject of intense scrutiny as a potential Kitaev quantum spin liquid, predicted to display Majorana fermions as low energy excitations. In practice, $\alpha$-RuCl$_3$ undergoes a transition to a…
The conjecture made recently by the group at Sherbrooke, that their observed anomalous thermal Hall effect in the pseudo-gap phase in the cuprates is due to phonons, is supported on the basis of an earlier result that the observed…
We investigate both the longitudinal thermal conductivity ($\kappa_{xx}$) and the planar thermal Hall conductivity ($\kappa_{xy}$) in the Kitaev spin liquid candidate of Co-based honeycomb antiferromagnet Na$_2$Co$_2$TeO$_6$ in a magnetic…
The mechanism behind thermal Hall effects by phonons, which are observed in various materials, is not clarified despite the dominant contribution as heat carriers. Theoretically, mechanisms based on the intrinsic Berry phase and those on…