Related papers: Revealing Quadrupolar Excitations with Non-Linear …
We study numerically the two-dimensional coherent spectrum (2DCS) of the Tomonaga-Luttinger liquid hosted by the $S=1/2$ XY spin chain. The 2DCS characterizes the system's third order nonlinear magnetic response triggered by three pulses,…
We investigate the excitation spectra of a spin-1/2 antiferromagnetic Heisenberg trimer spin chain by employing a combination of numerical and theoretical techniques. Utilizing the Krylov-space correction-vector method in density matrix…
Coherent two-dimensional spectroscopy in IR or visible region is very effective for studying correlations, energy relaxation/transfer pathways in complex multi-chromophore or multi-mode systems. However it is usually restricted up to…
Recent studies have shown that the nonlinear optical response of crystalline systems is fundamentally a quantum geometric property. In this work, we propose two-dimensional coherent spectroscopy (2DCS), which measures the nonlinear…
We study electric field induced two-dimensional coherent nonlinear optical spectroscopy (2DCS) in a Kitaev magnet at finite temperature. We show that 2DCS is susceptible to both types of fractional quasiparticles of this quantum…
The excitation spectrum of the 2-leg S=1/2 Heisenberg ladder is examined perturbatively. Using an optimally chosen continuous unitary transformation we expand the Hamiltonian and the Raman operator about the limit of isolated rungs leading…
Multidimensional coherent optical spectroscopy is one of the most powerful tools for investigating complex quantum mechanical systems. While it was conceived decades ago in magnetic resonance spectroscopy using micro- and radio-waves, it…
The emergence of spinon quasiparticles, which carry spin but lack charge, is a hallmark of collective quantum phenomena in low-dimensional quantum spin systems. While the existence of spinons has been demonstrated through scattering…
We theoretically analyze two-dimensional coherent spectroscopy (2DCS) signals for disordered superconductors in two limits: One is the narrow-band limit with sinusoidal pulse waves, and the other is the broad-band limit with delta-function…
Longitudinal magnons are a distinct type of multipolar excitations in magnetic materials with large spins $S\ge 1$ and strong easy-axis anisotropy. These excitations have angular momentum $S^z = \pm 2S$ and can be viewed as a propagating…
We study the spin excitation spectra of the two-dimensional spin-$1/2$ Heisenberg model with a checkerboard structures using stochastic analytic continuation of the imaginary-time correlation function obtained from a quantum Monte Carlo…
We investigate theoretically and experimentally fluctuations of high spin (F>1/2) beyond the linear response regime and demonstrate dramatic modifications of the spin noise spectra in the high power density probe field. Several effects…
Two-dimensional coherent spectroscopy (2DCS) provides insights into the nonlinear response of correlated lattice systems. We simulate multipulse excitations in the Hubbard model using nonequilibrium dynamical mean-field theory to extract…
Spin-flip inelastic electron tunneling spectroscopy allows magnetic materials to be probed at the single-atom level via scanning tunneling microscopy. Previously, the local spectral weight of spin excitations of small systems has been…
Resonant inelastic x-ray spectroscopy (RIXS) has emerged as an important tool to explore magnetism in two-dimensional (2D) antiferromagnet realized in strongly correlated materials. Here we consider the Heisenberg model with nearest and…
Spectral densities are computed in unprecedented detail for quantum antiferromagnetic spin 1/2 two-leg ladders. These results were obtained due to a major methodical advance achieved by optimally chosen unitary transformations. The approach…
The identification of fractionalized excitations in quantum spin liquids (QSLs) remains a central challenge in condensed matter physics. In dipolar-octupolar (DO) pyrochlores, such as $\text{Ce}_2\text{Zr}_2\text{O}_7$, the candidate…
We study the excitation spectrum of the $S=1/2$ Heisenberg model on the randomly diluted square lattice by analytic continuation of QMC data. At dilution fractions $p=1/16$ and $p=1/8$, the dynamic structure factor $S({\bf q},\omega)$…
The magnetic excitations of the quasi-2D spin-1/2 Heisenberg antiferromagnet on an anisotropic triangular lattice Cs2CuCl4 are explored throughout the 2D Brillouin zone using inelastic neutron scattering. In the spin liquid phase above the…
Using high-resolution resonant inelastic x-ray scattering (RIXS), we performed a momentum-resolved study of magnetic excitations in the model spin-1/2 2D antiferromagnetic insulator Sr_2CuCl_2O_2. We identify both a single-spin-wave feature…