Multiple mobile excitons manifested as sidebands in quasi-one-dimensional metallic TaSe.

Charge neutrality and their expected itinerant nature makes excitons potential transmitters of information. However, exciton mobility remains inaccessible to traditional optical experiments that only create and detect excitons with negligible momentum. Here, using angle-resolved photoemission spectroscopy, we detect dispersing excitons in the quasi-one-dimensional metallic trichalcogenide, TaSe.

Proximity-Induced Novel Ferromagnetism Accompanied with Resolute Metallicity in NdNiO Heterostructure.

Employing X-ray magnetic circular dichroism (XMCD), angle-resolved photoemission spectroscopy (ARPES), and momentum-resolved density fluctuation (MRDF) theory, the magnetic and electronic properties of ultrathin NdNiO (NNO) film in proximity to ferromagnetic (FM) La Sr MnO (LSMO) layer are investigated. The experimental data shows the direct magnetic coupling between the nickelate film and the manganite layer which causes an unusual ferromagnetic (FM) phase in NNO. Moreover, it is shown the metal-insulator transition in the NNO layer, identified by an abrupt suppression of ARPES spectral weight near the Fermi level (E ), is absent.

Strain engineering of the charge and spin-orbital interactions in SrIrO.

In the high spin-orbit-coupled SrIrO, the high sensitivity of the ground state to the details of the local lattice structure shows a large potential for the manipulation of the functional properties by inducing local lattice distortions. We use epitaxial strain to modify the Ir-O bond geometry in SrIrO and perform momentum-dependent resonant inelastic X-ray scattering (RIXS) at the metal and at the ligand sites to unveil the response of the low-energy elementary excitations. We observe that the pseudospin-wave dispersion for tensile-strained SrIrO films displays large softening along the [h,0] direction, while along the [h,h] direction it shows hardening.

Topological Magnetic Phase in the Candidate Weyl Semimetal CeAlGe.

We report the discovery of topological magnetism in the candidate magnetic Weyl semimetal CeAlGe. Using neutron scattering we find this system to host several incommensurate, square-coordinated multi-k[over →] magnetic phases below T_{N}. The topological properties of a phase stable at intermediate magnetic fields parallel to the c axis are suggested by observation of a topological Hall effect.