Related papers: Disentangling Intertwined Embedded States and Spin…
Generalizing a covariant framework previously developed, it is shown that confinement insures that meson $\to q+\bar{q}$ decay amplitudes vanish when both quarks are on-shell. Regularization of singularities in a covariant linear potential…
We introduce an entanglement entropy analysis to quantitatively identify the confinement and deconfinement of the spinons in the spin excitations of quantum magnets. Our proposal is implemented by the parton construction of a…
The photon helicity may be mapped to a spin-1/2, whereby we put forward an intrinsic interaction between a polarized light beam as a ``photon spin current'' and a pure spin current in a semiconductor, which arises from the spin-orbit…
The nearest-neighbor quantum-antiferromagnetic (AF) Heisenberg model for spin 1/2 on a two-dimensional square lattice is studied in the auxiliary-fermion representation. Expressing spin operators by canonical fermionic particles requires a…
We study the light-front covariance of a vector-meson decay constant using a manifestly covariant fermion field theory model in $(3+1)$ dimensions. The light-front zero-mode issues are analyzed in terms of polarization vectors and method of…
Resonant inelastic light scattering experiments access the low lying excitations of electron liquids in the fractional quantum Hall regime in the range $2/5 \geq \nu \geq 1/3$. Modes associated with changes in the charge and spin degrees of…
Using the framework of the Covariant Spectator Theory (CST) [1] we are developing a covariant model formulated in Minkowski space to study mesonic structure and spectra. Treating mesons as effective $q\bar{q}$ states, we focused in [2] on…
We show the boundedness of entanglement entropy for (bipartite) pure states of quantum spin chains implies split property of subsystems. As a corollary the infinite volume ground states for 1-dim spin chains with the spectral gap between…
This work is a continuation of our recent study of non-relativistic charged particles, confined to a sphere enclosing a magnetic dipole at its center. In this sequel, we extend our computations in two significant ways. The first is to a…
For a two-component bosonic system, the components can be mapped onto a pseudo-spin degree of freedom with spin quantum number S=1/2. We provide a rigorous proof that for a wide-range of real Hamiltonians with component independent mass and…
We performed a Lorentz covariant quantization of the spin-1/2 fermion field assuming the space-like energy-momentum dispersion relation. We a\-chieved the task in the following steps: ($i$) determining the unitary realizations of the…
Exchange processes are responsible for the stability of elementary boson condensates with respect to their possible fragmentation. This remains true for composite bosons when single fermion exchanges are included but spin degrees of freedom…
We suggest a possible algorithm to calculate one-loop n-point functions within a variant of light-front perturbation theory. The key ingredients are the covariant Passarino-Veltman scheme and a surprising integration formula that localises…
We investigate the feasibility of many candidate quantum Hall states for two-component bosons in the lowest Landau level. We identify interactions for which spin-singlet incompressible states occur at filling factors $\nu=2/3$, 4/5 and 4/3,…
We analyze the indirect exchange interaction between two two-state systems, e.g., spins 1/2, subject to a common finite-temperature environment modeled by bosonic modes. The environmental modes, e.g., phonons or cavity photons, are also a…
The prospect of developing magnetic qubits is discussed. The first part of the article makes suggestions on how to achieve the coherent quantum superposition of spin states in small ferromagnetic clusters, weakly uncompensated…
We discuss anomalous decoherence effects at zero and finite temperatures in driven coupled quantum spin systems. By numerical simulations of the quantum master equation, it is found that the entanglement of two coupled spin qubits exhibits…
A first principles calculation of the quantum corrections to the electric charge of a dyon in an N=2 gauge theory with arbitrary gauge group is presented. These corrections arise from the fermion fields via the mechanism of fermion…
Intrinsic spin currents are encountered in noncentrosymmetric crystals without any external electric fields; these currents are caused by spin-orbit interaction. In this paper, various theoretical aspects of this phenomenon in bulk…
Quantum magneto-oscillations provide a powerfull tool for quantifying Fermi-liquid parameters of metals. In particular, the quasiparticle effective mass and spin susceptibility are extracted from the experiment using the Lifshitz-Kosevich…