arXiv subjects

Yuqing Cao

Publications and source records attributed to Yuqing Cao.

4 recordsLinked to original sources

arXiv2026

Noncollinear spin textures and 90{\deg} domain walls in twisted XY magnets

Twisted moir\'e magnets are promising in exploring noncollinear magnetic phases, yet current experimental studies have been restricted to uniaxial magnets, limiting the accessible phase space. Here, we demonstrate noncollinear moir\'e magnetism based on XY magnet CrCl3. The tunneling magnetoconductance of twisted CrCl3 exhibits multiple field-driven transitions in small-twist-angle devices, attributed to the coexisting antiferromagnetic and ferromagnetic domains with distinct susceptibilities. The inferred spin configuration depends on the layer number, reflecting the interlayer coupling strength between twisted layers. This moir\'e magnetism is remarkably robust, persisting up to twisted double nine-layer stacks. Combined with micromagnetic simulations, we identify the ground state as the predicted "twisted-s" phase featuring 90{\deg} domain walls. Finally, we demonstrate voltage control of these noncollinear phases, highlighting the electrically tunable twist-spintronics.

cond-mat.mes-hall↗

arXiv2026

Rapid tracking through strongly scattering media with physics-informed neuromorphic speckle analysis

This work addresses the critical problem of tracking fast-moving objects through strongly scattering media in a low-light environment. Different from existing approaches that use frame-based cameras with fixed exposure times, which trade off signal-to-noise ratio for temporal resolution, we introduce computational neuromorphic tracking (CNT), a physics-informed framework that combines asynchronous event sensing with task-driven speckle analysis for robust motion estimation. We formulate the neuromorphic speckle aggregation as a spatiotemporal speckle representation, jointly optimizing the temporal and spatial parameters to maximize tracking stability under extreme conditions. Extensive experiments demonstrate that our method enables robust motion tracking of 10x faster motion and under 10x dimmer illumination compared to conventional systems. These improvements significantly broaden the operational regime for tracking through scattering media, providing an efficient and scalable solution for demanding scenarios involving rapid motion and low-light conditions.

cs.CV↗

arXiv2026

Pressure-induced superconductivity in topological insulator Ge2Bi2Te5 and the evolution with Mn doping

Introducing superconductivity (SC) or magnetism into topological insulators (TIs) can give rise to novel quantum states and exotic physical phenomena. Here, we report a high-pressure transport study on the TI Ge2Bi2Te5 and its Mn-doped counterparts. The application of pressure induces a SC in Ge2Bi2Te5, which shows a dome-shape phase diagram with the maximum Tc of 7.6 K at 23 GPa. Doping Mn into Ge2Bi2Te5 introduces an antiferromagnetic order at ambient pressure and strongly weakens the pressure-induced SC, demonstrating that magnetism and SC compete in this material system. Present study provides a new platform for investigating the interplay among band topology, magnetism, and SC.

cond-mat.supr-con↗

arXiv2026

Three-dimensional topological insulator feature of ternary chalcogenide Ge2Bi2Te5

The exploration of novel topological insulators (TIs) beyond binary chalcogenides has been accelerated in pursuit of exotic quantum states and device applications. Here, the layered ternary chalcogenide Ge2Bi2Te5 is identified as a three-dimensional TI. The bulk electronic structure of Ge2Bi2Te5 features a hole-type Fermi surface at Fermi level EF, which dominates the transport properties. Moreover, an unoccupied topological surface state with a Dirac point located at 290 meV above EF has been observed. Theoretical calculations confirm a bulk bandgap and a nontrivial Z2 topological invariant (000;1). The present study demonstrates that the material family of layered tetradymite-like ternary compounds is an important platform to explore exotic topological phenomena.

cond-mat.str-el↗