This thesis is devoted to the investigation of static and dynamic properties of
two different sets of quantum magnets with neutron scattering techniques and
the help of linear spin wave theory.
Both systems are copper-based with spin-1/2, which makes them ...
Spin dynamics in skyrmion hosting materials provide novel functionality in magnonics because of the formation of a novel magnon band structure and the nanoscale sizes of magnetic skyrmions. In this thesis, we explore the spin dynamics in the chiral magnet ...
In magnetism, skyrmions correspond to classical three-dimensional spin textures characterized by a topological invariant that keeps track of the winding of the magnetization in real space, a property that cannot be easily generalized to the quantum case si ...
Vector-chiral (VC) antiferromagnetism is a spiral-like ordering of spins which may allow ferroelectricity to occur due to loss of space inversion symmetry. In this Letter we report direct experimental observation of ferroelectricity in the VC phase of beta ...
By combining two independent approaches, inelastic neutron-scattering measurements and density-functionaltheory calculations, we study the spin waves in the collinear antiferromagnetic phase (AFM2) of Mn5Si3. We obtain its magnetic ground-state properties ...
Magnons (spin waves, SWs) are elementary spin excitations in magnetically ordered materials. They are the promising quanta for the transmission and processing of information. Magnons can be coupled to the electromagnetic waves utilized for the wireless com ...
This thesis presents results of studies of novel compounds modeling complex fundamental physics phenomena. Cu2OSO4 is a copper based magnetic Mott Insulator system, where spin half magnetic moments form a new type of lattice. These intrinsically quantum pi ...
In the three-dimensional (3D) Heisenberg model, topological point defects known as spin hedgehogs behave as emergent magnetic monopoles, i.e., quantized sources and sinks of gauge fields that couple strongly to conduction electrons, and cause unconventiona ...
Magnetic skyrmions are vortexlike topological spin textures often observed in structurally chiral magnets with Dzyaloshinskii-Moriya interaction. Among them, Co-Zn-Mn alloys with a beta-Mn-type chiral structure host skyrmions above room temperature. In thi ...
We use neutron scattering to show that ferromagnetism and antiferromagnetism coexist in the low T state of the pyrochlore quantum magnet Yb2Ti2O7. While magnetic Bragg peaks evidence long-range static ferromagnetic order, inelastic scattering shows that sh ...
We report a small-angle neutron scattering study of the helical and skyrmion lattice order in single-crystal Cu2OSeO3 under quasihydrostatic helium gas pressures up to 5 kbar. By using helium gas as the pressure-transmitting medium (PTM) we ensure pressure ...
Motivated by the recently observed intriguing mode splittings in a magnetic field with inelastic neutron scattering in the spin ladder compound (C5H12N)(2) CuBr4 (BPCB), we investigate the nature of the spin ladder excitations using a density matrix renorm ...
