相关论文: Magnetic order induced polarization anomaly of Ram…
The coupling between spin and charge degrees of freedom in a crystal imparts strong optical signatures on scattered electromagnetic waves. This has led to magneto-optical effects with a host of applications, from the sensitive detection of…
The discovery of 2-dimensional (2D) materials, such as CrI3, that retain magnetic ordering at monolayer thickness has resulted in a surge of research in 2D magnetism from both pure and applied perspectives. Here, we report a magneto-Raman…
We apply the density-functional theory to study various phases (including non-magnetic (NM), anti-ferromagnetic (AFM), and ferromagnetic (FM)) in monolayer magnetic chromium triiodide (CrI$_3$), a recently fabricated 2D magnetic material.…
We use a combination of polarized Raman spectroscopy experiment and model magnetism-phonon coupling calculations to study the rich magneto-Raman effect in the two-dimensional (2D) magnet $\mathrm{CrI_3}$. We reveal a novel…
Exciton dynamics can be strongly affected by lattice vibrations through electron-phonon coupling. This is rarely explored in two-dimensional magnetic semiconductors. Focusing on bilayer CrI3, we first show the presence of strong…
We find unusually large cross-polarized (and anti-symmetric) Raman signature of A$_{\rm g}$ phonon mode in CrI$_3$, in agreement with experiments. The signal is present only when the following three effects are considered in concert:…
Magnetic order typically emerges due to the short-range exchange interaction between the constituent electronic spins. Recent discoveries have found a crucial role for spin-phonon coupling in various phenomena from optical ultrafast…
Magneto-optical effect refers to a rotation of polarization plane, which has been widely studied in traditional ferromagnetic metal and insulator films and scarcely in two-dimensional layered materials. Here we uncover a new nonreciprocal…
Raman study on a select few orthochromites, RCrO$_3$ (R = Y, Lu, Gd, Eu and Sm) shows that the phonon behavior at TN in compounds with magnetic R-ion (Gd and Sm) is remarkably different from that of non-magnetic R-ion (Y, Lu and Eu). While…
Exfoliated chromium triiodide (CrI$_3$) is a layered van der Waals (vdW) magnetic insulator that consists of ferromagnetic layers coupled through antiferromagnetic interlayer exchange. The resulting permutations of magnetic configurations…
We study the Raman spectrum of CrI$_3$, a material that exhibits magnetism in a single-layer. We employ first-principles calculations within density functional theory to determine the effects of polarization, strain, and incident angle on…
In this paper, we show that photoluminescence from CrCl3 bulk crystal exhibits a preferential polarization direction when films are magnetically ordered or strained. We verify the magnetization as responsible for the polarization by…
We report on the lattice and spin dynamics in the monopnictide CrAs using polarized Raman scattering. This system exhibits a first-order magneto-structural phase transition at T_N~ 265 K, below which the magnetic moments of Cr form an…
The role of dipolar interactions and anisotropy are important to obtain, otherwise forbidden, ferromagnetic ordering at finite temperature for ions arranged in two-dimensional (2D) arrays (monolayers). Here we demonstrate that conventional…
Magnetic systems with noncentrosymmetric crystal structures are renowned for their complex magnetic ordering and diverse and fascinating physical properties. In this report, we provide a comprehensive study of the chiral magnetic system…
Polarized Raman scattering and infrared reflection spectra of hexagonal HoMnO$_3$ single crystals in the temperature range 10-300 K are reported. Group-theoretical analysis is performed and scattering selection rules for the second order…
Spin-phonon coupling, the interaction of spins with surrounding lattice is a key parameter to understand the underlying physics of multiferroics and engineer their magnetization dynamics. Elementary excitations in multiferroic materials are…
Temperature dependent Raman scattering measurements have been performed to explore unusual coupling between magnetism and crystal structure in doped pyrochlore iridate Y$_2$(Ir$_{1-x}$Ru$_x$)$_2$O$_7$ with $x$ = 0.0, 0.05 and 0.2. The…
We determine the nature of coupled phonons and magnetic excitations in AlFeO3 using inelastic light scattering from 5 K to 315 K covering a spectral range from 100-2200 cm-1 and complementary first-principles density functional theory-based…
The discovery of two-dimensional (2D) systems hosting intrinsic long-range magnetic order represents a seminal addition to the rich physical landscape of van der Waals (vdW) materials. CrI3 has emerged as perhaps the most salient example,…