Title Information
Title
Uncovering Novel Phases in Complex Magnetic Materials Using Resonant X-ray Scattering
Type of Resource (primo)
dissertations
Name: Personal
Name Part
Zager, Benjamin
Role
Role Term: Text
creator
Name: Personal
Name Part
Plumb, Kemp
Role
Role Term: Text
Advisor
Name: Personal
Name Part
Marston, Brad
Role
Role Term: Text
Reader
Name: Personal
Name Part
Weber, Peter
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Department of Physics
Role
Role Term: Text
sponsor
Origin Information
Copyright Date
2024
Physical Description
Extent
17, 180 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2024
Genre (aat)
theses
Abstract
Materials with strongly interacting electrons exhibit a wide variety of unconventional ordering phenomena that are both fundamentally rich and promising for many potential technological applications. These phases often involve coupling between spin, charge, orbital, and lattice degrees of freedom, precisely tuned by a hierarchy of energy scales. They may also involve more subtle degrees of freedom that may be elusive to many common experimental probes. In this thesis, I discuss a series of resonant elastic and inelastic x-ray scattering experiments (REXS/RIXS) on complex magnetic materials to uncover the microscopic mechanisms behind the novel magnetic phenomena observed in these materials. NiRh2O4 is a S=1 frustrated diamond lattice antiferromagnet that may be in proximity to a quantum critical point. I carried out RIXS measurements to unravel the spin-orbital-lattice entangled ground state in NiRh2O4. CoNb3S6 is an intercalated transition metal dichalcogenide (iTMD) exhibiting a giant anomalous Hall effect (AHE) that cannot be explained by its putative collinear antiferromagnetic order. Using REXS, I discovered a long-wavelength modulation of the magnetic structure that gives rise to a novel striped pattern in the scalar spin chirality. The properties of iTMDs are highly sensitive to the precise stoichiometry of intercalated 3d ions. I carried out comprehensive magnetic and structural characterization on CoNb3S6 and the related material NiNb3S6 with varying Co and Ni stoichiometry to understand the dependence of the magnetic properties on sample composition. NiGa2S4 is a nearly ideal S=1 triangular lattice magnet which shows no long range magnetic order and exhibits a variety of unconventional magnetic properties. I carried out REXS measurements to probe the magnetic correlations within a small sample volume to disentangle structural and magnetic disorder. I find a correlation length that is longer than that found in previous measurements, as well as a temperature-induced shift in the magnetic wavevector. Using RIXS, I ruled out the previously reported negative charge transfer ground state and instead found a mixed valence state.
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00874449")
Topic
Condensed matter--Magnetic properties
Subject
Topic
quantum materials
Subject
Topic
condensed matter physics
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01181885")
Topic
X-rays--Scattering
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01181847")
Topic
X-ray spectroscopy
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20240521