Related Experiment Video
Updated: Aug 6, 2026
04:51
Comparison of Two Different Synthesis Methods of Single Crystals of Superconducting Uranium Ditelluride
Published on: July 8, 2021
Pseudo point nodal superconducting gap in spin-triplet UTe2
S Hosoi1, K Imamura2,3, M M Bordelon2
1Los Alamos National Laboratory, Los Alamos, NM, USA. shosoi@lanl.gov.
Nature Communications
|July 16, 2026
Summary
This study reveals Uranium Ditelluride (UTe2) has a fully gapped superconducting state, not point nodes. This finding clarifies its exotic pairing mechanism and order parameter symmetry.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Superconductivity
Background:
- UTe2 is an unconventional heavy-fermion superconductor.
- It is a candidate for spin-triplet pairing.
- Conflicting reports on its gap structure hinder understanding of its order parameter symmetry.
Purpose of the Study:
- To definitively resolve the gap anisotropy in UTe2.
- To constrain the order parameter and exotic pairing mechanism.
Main Methods:
- Measurements of b-axis thermal conductivity (κb/T) on high-quality UTe2 single crystals.
- Experiments conducted down to ~50 mK.
- Application of magnetic fields (H∥a).
Main Results:
- Negligible residual conductivity (κb/T) as temperature approaches 0 K.
- Weak enhancement of residual term under magnetic fields.
- Observation of a threshold-like field scale with a kink, signaling a change in quasiparticle transport.
- Development of strong anisotropy in transport above the threshold field.
Conclusions:
- UTe2 hosts a fully gapped superconducting state.
- The gap features pseudo point nodes, approaching but not reaching zero.
- These findings place strong constraints on the order parameter and exotic pairing mechanism.
More Related Videos
Related Concept Videos
01:03Atomic Nuclei: Nuclear Spin State Overview
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
01:14Atomic Nuclei: Nuclear Spin State Population Distribution
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
01:22Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
Vicinal or three-bond coupling is commonly observed between protons attached to adjacent carbons. Here, nuclear spin information is primarily transferred via electron spin interactions between adjacent C‑H bond orbitals. This generally favors the antiparallel arrangement of spins, so 3J values are usually positive.
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
01:08Spin–Spin Coupling Constant: Overview
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...