Related papers: Reversable phase transitions in ferroic two-dimens…
We studied dielectric properties of a polar nematic phase (NF) sandwiched between two gold or ITO electrodes, serving as a cell surfaces. In bulk, NF is expected to exhibit a Goldstone mode (phason), because polarization can uniformly…
Optical two-dimensional Fourier-transformed (2DFT) spectroscopy is used to study the coherent optical response of potassium vapor in a thin transmission cell. Rephasing and non-rephasing spectra of the D1 and D2 transitions are obtained and…
The structure and polarization of the as-yet hypothetical Ruddlesden-Popper compound Pb$_2$TiO$_4$ are investigated within density-functional theory. Zone enter phonons of the high-symmetry K$_2$NiF$_4$-type reference structure, space group…
In the realm of modern materials science and advanced electronics, ferroelectric materials have emerged as a subject of great intrigue and significance, chiefly due to their remarkable property of reversible spontaneous polarization. This…
The quasi-one-dimensional material Bi4I4 hosts two crystallographically similar polymorphs that realize distinct topological insulating phases separated by a first-order structural transition near room temperature. This transition occurs…
Using the Landau-Ginzburg-Devonshire approach, we study light-induced phase transitions, evolution of polar state and domain morphology in photo-ferroelectric nanoparticles (NPs). Light exposure increases the free carrier density near the…
Optoelectronic components with adjustable parameters, from variable-focal-length lenses to spectral filters that can change functionality upon stimulation, have enormous technological importance. Tuning of such components is conventionally…
The distorted phases of monolayer 1T-MoS$_2$ have distinct electronic properties, with potential applications in optoelectronics, catalysis, and batteries. We theoretically investigate the use of Ni-doping to generate distorted 1T phases,…
The ability to reversibly toggle between two distinct states in a non-volatile method is important for information storage applications. Such devices have been realized for phase-change materials, which utilizes local heating methods to…
Materials combining electrically switchable ferroelectricity and tunable topological states hold significant promise for advancing both foundamental quantum phenomena and innovative device architectures. Here, we employ first-principles…
Ultrafast optical control of the structural and electronic properties of various quantum materials has recently sparked great interest. In particular, photoinduced quantum phase transition between distinct topological phases has been…
In ferroelastic materials, spontaneous symmetry breaking leads to the formation of twin domains. Although the bulk crystal typically remains centrosymmetric, inversion symmetry can be locally broken at the domain walls, potentially changing…
Two-photon excitation (TPE) proceeds via a "virtual" pathway, which depends on the accessibility of one or more intermediate states, and, in the case of non-centrosymmetric molecules, an additional "dipole" pathway involving the…
We demonstrate midinfrared second-harmonic generation as a highly sensitive phonon spectroscopy technique that we exemplify using $\alpha$-quartz (SiO$_2$) as a model system. A midinfrared free-electron laser provides direct access to…
The discovery of two-dimensional (2D) materials possessing switchable spontaneous polarization with atomic thickness opens up exciting opportunities to realize ultrathin, high-density electronic devices with potential applications ranging…
Nonlinear phononics relies on the resonant optical excitation of infrared-active lattice vibrations to coherently induce targeted structural deformations in solids. This form of dynamical crystal-structure design has been applied to control…
We demonstrate a new concept for reconfigurable nanophotonic devices exploiting ultrafast nonlinear control of shaped wavefronts in a multimode nanomaterial consisting of semiconductor nanowires. Femtosecond pulsed laser excitation of the…
We investigate the properties of oxygen-functionalized carbides of lanthanide elements with the composition M2CO2 (M=Gd, Tb,Dy) that form two-dimensional (2D) structures. Our ab initio calculations reveal that oxygen termination turns M2C…
Ferroelectric switching in BiFeO$_3$ multiferroic thin films with intrinsic ``stripe-like'' and ``bubble-like'' polydomain configurations was studied by piezoresponse force microscopy. Using the local electric field applied by a scanning…
Quantum interference gives rise to the asymmetric Fano resonance line shape when the final states of an electronic transition follows within a continuum of states and a discrete state, which has significant applications in optical switching…