标题： UTe2的电子维度 显示英文标题

标题： Electronic dimensionality of UTe2

摘要： 重费米子金属UTe2中的超导性在非常高的磁场下仍然存在，这既是一个引人入胜的谜题，也是一个实验挑战。 磁场的强烈且非微扰的影响使高场相中确定超导序参量变得复杂。 在这里，我们报告了沿b轴施加高达45特斯拉磁场时，在精确对齐的微棒中测量到的电子输运各向异性。 我们的结果揭示了场增强相中高度方向性的涡旋钉扎力。 对于沿c方向的电流，临界电流显著受到抑制，而稍微角度错位时，流体流动电压会减少——这些特征通常在准二维超导体（如铜氧化物和铁基超导体）中看到的涡旋锁定转变的标志。 这些发现挑战了UTe2中电荷传输几乎各向同性的假设，并指向高场态中二维性的增强，这与序参量的变化是一致的。 在高场状态下，类似于配对密度波的状态自然会导致超流体密度的层状调制，形成平面结构，这些结构限制涡旋并在流体流动状态下引导它们的滑动。 显示英文摘要

摘要： Superconductivity in the heavy-fermion metal UTe2 survives the application of very high magnetic fields, presenting both an intriguing puzzle and an experimental challenge. The strong, non-perturbative influence of the magnetic field complicates the determination of superconducting order parameters in the high-field phases. Here, we report electronic transport anisotropy measurements in precisely aligned microbars in magnetic fields to 45 T applied along the b-axis. Our results reveal a highly directional vortex pinning force in the field-reinforced phase. The critical current is significantly suppressed for currents along the c direction, whereas the flux-flow voltage is reduced with slight angular misalignments--hallmarks of vortex lock-in transitions typically seen in quasi-2D superconductors like cuprates and pnictides. These findings challenge the assumption of nearly isotropic charge transport in UTe2 and point to enhanced two-dimensionality in the high-field state, consistent with a change in the order parameter. A pair-density-wave-like state at high fields could naturally induce a layered modulation of the superfluid density, forming planar structures that confine vortices and guide their sliding in the flux-flow regime.