English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

There is considerable evidence that the superconducting state ofSr$_2$RuO$_4$ breaks time reversal symmetry. In the experiments showing timereversal symmetry breaking its onset temperature, $T_\text{TRSB}$, is generallyfound to match the critical temperature, $T_\text{c}$, within resolution. Incombination with evidence for even parity, this result has led to considerationof a $d_{xz} \pm id_{yz}$ order parameter. The degeneracy of the two componentsof this order parameter is protected by symmetry, yielding $T_\text{TRSB} =T_\text{c}$, but it has a hard-to-explain horizontal line node at $k_z=0$.Therefore, $s \pm id$ and $d \pm ig$ order parameters are also underconsideration. These avoid the horizontal line node, but require tuning toobtain $T_\text{TRSB} \approx T_\text{c}$. To obtain evidence distinguishingthese two possible scenarios (of symmetry-protected versus accidentaldegeneracy), we employ zero-field muon spin rotation/relaxation to study pureSr$_2$RuO$_4$ under hydrostatic pressure, and Sr$_{1.98}$La$_{0.02}$RuO$_4$ atzero pressure. Both hydrostatic pressure and La substitution alter $T_\text{c}$without lifting the tetragonal lattice symmetry, so if the degeneracy issymmetry-protected $T_\text{TRSB}$ should track changes in $T_\text{c}$, whileif it is accidental, these transition temperatures should generally separate.We observe $T_\text{TRSB}$ to track $T_\text{c}$, supporting the hypothesis of$d_{xz} \pm id_{yz}$ order.

Unsplit superconducting and time reversal symmetry breaking transitions in Sr$_2$RuO$_4$ under hydrostatic pressure and disorder