Related papers: Emergence of Charge Loop Current in Geometrically …
Unconventional symmetry-breaking phenomena due to nontrivial order parameters attract increasing attention in strongly correlated electron systems. Here, we predict theoretically the occurrence of nanoscale spontaneous spin-current, called…
We study the emergence of charge ordered phases within a pi-loop current (piLC) model for the pseudogap based on a three-band model for underdoped cuprate superconductors. Loop currents and charge ordering are driven by distinct components…
Recent experiments on geometrically frustrated kagome metal AV3Sb5 (A=K, Rb, Cs) have revealed the emergence of the charge loop current (cLC) order near the bond order (BO) phase. However, the origin of the cLC and its relation to other…
Unconventional symmetry breaking without spin order,such as the rotational symmetry breaking (=nematic or smectic) orders as well as the spontaneous loop-current orders, have been recently reported in cuprate superconductors and their…
The recent experimental observations of loop current in Sr$_{2}$IrO$_{4}$, YBa$_{2}$Cu$_{3}$O$_{7}$, and Sr$_{14}$Cu$_{24}$O$_{41}$ have inspired a theoretical study that broadly redefines loop current as a manifestation of quantum liquid…
A chiral spin liquid (CSL) phase has been recently reported in the Hubbard model on a triangular lattice at half-filling. It emerges in an intermediate coupling regime, which is sandwiched between a $120^\circ$ antiferromagnetic (AFM) phase…
Charge fluctuations in the quasi-one-dimensional material Li0.9Mo6O17 are analyzed based on a multi orbital extended Hubbard model. A charge ordering transition induced by Coulomb repulsion is found with a charge ordering pattern different…
Orbital magnetism and the loop currents (LC) that accompany it have been proposed to emerge in many systems, including cuprates, iridates, and kagome superconductors. In the case of cuprates, LCs have been put forward as the driving force…
This thesis deals with the Hubbard model as prototypical model to describe the physics of electrons in the two-dimensional copper-oxide planes of high-$T_c$ cuprates. To get approximate solutions, we employ functional renormalization group…
We derive an efficient and unbiased method for computing order parameters in correlated electron systems with competing instabilities. Charge, magnetic and pairing fluctuations above the energy scale of spontaneous symmetry breaking are…
We investigate the possibility of ferromagnetic ordering in the non-degenerate Hubbard model on the face-centered cubic lattice within the functional renormalization group technique using temperature as a scale parameter. We assume the…
We review recent progress in understanding the different spatial broken symmetries that occur in the normal states of the family of charge-transfer solids (CTS) that exhibit superconductivity (SC), and discuss how this knowledge gives…
Unconventional superconductivity (SC) characterized by multi-fermion orderings has attracted substantial attention. However, previous studies have largely focused on 2D systems or 3D systems with effective 2D symmetries. Here, we…
Effects of geometrical frustration in low-dimensional charge ordering systems are theoretically studied, mainly focusing on dynamical properties. We treat extended Hubbard models at quarter-filling, where the frustration arises from…
The recent discovery of a variety of intricate electronic order in kagome metals has sprouted significant theoretical and experimental interest. From an electronic perspective on the potential microscopic origin of these phases, the most…
Disorder in materials may be used to tune their functionalities, but much more strikingly, its presence can entail entirely new behavior. This happens in charge-ice where structural disorder is not weak and local, but strong and long-range…
We study current-current correlations in the three-band Hubbard model for two-leg CuO ladders using the density-matrix renormalization group method. We find that these correlations decrease exponentially with distance for low doping but as…
Frustration is a key driver of exotic quantum phases, yet its role in charge dynamics remains largely unexplored. We show that charge frustration - induced by electronic polarization effects - stabilizes unconventional insulating states in…
This thesis comprises two parts centered around the functional renormalization-group framework: in the first part, I study the role of symmetries and conservation laws in approximate solutions, while in the second part I analyze Friedel…
When studying the collective motion of biological groups a useful theoretical framework is that of ferromagnetic systems, in which the alignment interactions are a surrogate of the effective imitation among the individuals. In this context,…