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تسجيل مستخدم جديدCoexistence of superconductivity with exotic ferromagnetic state in pressurized non-superconducting UTe$_2$
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The discovery of superconductivity in heavy Fermion UTe$_2$, a candidate topological and triplet-paired superconductor, has aroused widespread interest. However, to date, superconductivity has only been reported in nonstoichiometric crystals of UTe$_2$ with a Te deficit. Here, we demonstrate that the application of uniaxial pressure induces superconductivity in stoichiometric UTe$_2$ crystals. Measurements of resistivity, magnetoresistance and susceptibility reveal that uniaxial pressure results in a suppression of the Kondo coherent state seen at ambient pressure, leading to the emergence of superconductivity initially at 1.5 GP, followed by the development of bulk superconductivity at 4.8 GPa. The superconducting state coexists with an exotic ferromagnetically ordered (FM) state that develops just below the onset temperature of the superconducting transition. High-pressure synchrotron x-ray diffraction measurements performed at 20 K indicate that no structural phase transition occurs over the measured pressure range. Our results not only demonstrate the coexistence of superconductivity with an exotic ferromagnetic state in pressurized stoichiometric UTe$_2$, but also highlight a vital role of Te deficiency in developing superconductivity at ambient pressures.
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