Mechanism of field-reentrant superconductivity in $\mathrm{UTe_2}$ above 400 kG

In plain words

In $\mathrm{UTe_2}$, superconductivity reappears in magnetic fields of about 400 to 650 kG when the field is tilted at a particular angle, fields far above those that destroy ordinary superconductors.

Precise statement

In $\mathrm{UTe_2}$ with the field tilted from the b axis toward c by roughly 20 to 40 degrees, superconductivity reappears above the metamagnetic transition $H_m \sim 350\,\mathrm{kG}$ and survives to $\sim 650\,\mathrm{kG}$ (Ran et al., Nature Physics 2019). Determine the pairing mechanism and order parameter of this field-polarized phase: triplet pairing mediated by field-enhanced ferromagnetic fluctuations, compensation of the exchange field by the applied field (Jaccarino-Peter mechanism), or pairing on a Fermi surface reconstructed at $H_m$. An answer predicts the angular window and the upper critical field from a model with independently measured parameters.

What would settle it

Fermi-surface and magnetization measurements across $H_m$ combined with a calculation that reproduces the angular window and upper field of the reentrant phase.

Status in the literature

Unverified note: it names recent work and was partly written without a live literature search; it awaits a check by an editor.

Helm et al. (Nature Communications 2024) proposed field-induced compensation of magnetic exchange; no mechanism is agreed.

Revision history

Results

No results have been posted on this problem yet.

Post a result · how results are checked

Sign in to follow or save this problem

See also

Comments (0)

Comments are not records: they are not signed, stamped or logged. How comments work

No comments yet.

Sign in to comment.