Pressure-induced structural phase transition and new superconducting phase in UTe2

Abstract

We report on the crystal structure and electronic properties of the heavy fermion superconductor UTe2 at high pressure up to 11 GPa, as investigated by X-ray diffraction and electrical resistivity experiments. The X-ray diffraction measurements under high pressure using a synchrotron light source reveal anisotropic linear compressibility of the unit cell up to 3.5 GPa, while a pressure-induced structural phase transition is observed above 3.5-4GPa at room temperature, where the body-centered orthorhombic crystal structure with the space group Immm changes into a body-centered tetragonal structure with the space group I4/mmm. The molar volume drops abruptly at the critical pressure, while the distance between the first-nearest neighbor of U atoms increases, implying a switch from the heavy electronic states to the weakly correlated electronic states. Surprisingly, a new superconducting phase at pressures higher than 7 GPa was detected at Tsc above 2K with a relatively low upper-critical field, Hc2(0). The resistivity above 3.5GPa, thus, in the high-pressure tetragonal phase, shows a large drop below 230 K, which may also be related to a considerable change from the heavy electronic states to the weakly correlated electronic states.

11 pages, 9 figures

References in corpus (10)

• Superconductivity on the border of weak itinerant ferromagnetism in UCoGe
• Unconventional Superconductivity in Heavy Fermion UTe2
• Metamagnetic Transition in Heavy Fermion Superconductor UTe2
• Multiple Superconducting Phases and Unusual Enhancement of the Upper Critical Field in UTe2
• First Observation of de Haas-van Alphen Effect and Fermi Surfaces in Unconventional Superconductor UTe2
• Low-dimensional antiferromagnetic fluctuations in the heavy-fermion paramagnetic ladder UTe${}_2$
• Magnetic-Field-Induced Phenomena in the Paramagnetic Superconductor UTe${}_2$
• Magnetic Properties under Pressure in Novel Spin-Triplet Superconductor UTe2
• Enhancement and Discontinuity of Effective Mass through the First-Order Metamagnetic Transition in UTe${}_2$
• Metastable phase of UTe${}_2$ formed under high pressure above 5 GPa

Cited by in corpus (10)

• Quasi-2D Fermi surface in the anomalous superconductor UTe2
• A review of UTe${}_2$ at high magnetic fields
• Clear Reduction in Spin Susceptibility and Superconducting Spin Rotation for $H\parallel a$ in the Early-Stage Sample of Spin-Triplet Superconductor UTe${}_2$
• A quantum critical line bounds the high field metamagnetic transition surface in UTe${}_2$
• Incommensurate antiferromagnetism in UTe2 under pressure
• UTe${}_2$: a narrow band superconductor
• Metamagnetism in the high-pressure tetragonal phase of UTe${}_2$
• Intrinsic coherence length anisotropy in nickelate, and some pnictide, and chalcogenide superconductors
• Electronic structure of UTe${}_2$ under pressure
• Unconventional superconductivity emerging along with the strange-metal behavior in UAs2 under pressure