Evidence of intertwined pair density and charge density wave orders in UTe₂.

Abstract

The strongly correlated spin-triplet superconductor UTe₂ hosts an unusual magnetic-field-sensitive charge density wave (CDW) phase, positioning it as a compelling system for studying intertwined electronic orders. A central challenge is determining whether the observed charge modulations arise from a triplet pair density wave (PDW) order and, if so, how the anisotropic magnetic field response of triplet superconductivity is manifested in the CDW response. Here, using a scanning tunneling microscope equipped with a vector magnetic field, we systematically investigate the evolution and interrelation of distinct CDW orders. Complementing the previously identified incommensurate CDW peaks (<i>q_i</i>_=1,2,3), we resolve an additional set of nondispersive modulations (<i>p_i</i>_=1,2,3 and <i>h</i>_1,2) with distinct temperature and magnetic field dependencies. The <i>p_i</i> CDW peaks vanish near <i>T</i>_c, while the <i>q_i</i> peaks survive well above <i>T</i>_c but are progressively suppressed by magnetic field in an anisotropic manner. The critical fields of the <i>q_i</i> peaks mirror the directional hierarchy of <i>H</i>_c2, which suggests a PDW is present above the bulk <i>T</i>_c. This is consistent with a Landau free-energy picture where PDWs with wavevectors <i>p_i</i> form above the bulk <i>T</i>_c, leading to composite CDW orders with wavevector <i>q</i>_i. Below <i>T</i>_c, the coupling of PDWs and uniform superconductivity leads to the <i>p_i</i> CDWs. Together, these findings establish UTe₂ as a rare platform where both the parent PDW and descendant orders are directly resolved, enabling access to both the fundamental and emergent manifestations of PDW physics.