相关论文: A coherent phonon-induced hidden quadrupolar order…
Exciting atomic oscillations with light is a powerful technique to control the electronic properties of materials, leading to remarkable phenomena such as light-induced superconductivity and ultrafast insulator to metal transitions. Here we…
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…
Photoexcitation of single-layered La$_{0.5}$Mn$_{1.5}$MnO$_4$ has played a key role in understanding orbital ordering and non-thermal states in the manganites. However, while orbital ordering in La$_{0.5}$Sr$_{1.5}$MnO$_4$ breaks the…
A ferroelectric material often exhibits a soft transvers optical (TO) phonon mode which governs it phase transition. Charge coupling to this ferroelectric soft mode may further mediate emergent physical properties, including…
We use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa2Cu3O6.6. We find that when coherent interlayer transport is enhanced by optical…
I show a way to tune photo-nuclear cross section effectively and therefore achieve nuclear transitions "on demand". The method is based on combinatorial enhancement of multiphoton processes under intense conditions. Taking advantage of…
Heavy electronic states originating from the f atomic orbitals underlie a rich variety of quantum phases of matter. We use atomic scale imaging and spectroscopy with the scanning tunneling microscope (STM) to examine the novel electronic…
A phenomenological model for the 'hidden order' transition in the heavy Fermion material URu$_2$Si$_2$ is introduced. The 'hidden order' is identified as an incommensurate, momentum-carrying hybridization between the light hole band and the…
Electronic state and the Verwey transition in magnetite (Fe_3O_4) are studied using a spinless three-band Hubbard model for 3d electrons on the B sites with the Hartree-Fock approximation and the exact diagonalisation method.…
Unconventional superconductivity in the cuprates emerges from, or coexists with, other types of electronic order. However, these orders are sometimes invisible because of their symmetry. For example, the possible existence of superfluid…
Intense ultrafast laser excitation can produce transient states of condensed matter that would otherwise be inaccessible. At high excitation level, the interatomic forces can be altered resulting in an unusual lattice dynamics. Here we…
Nonequilibrium hidden states, both transient and long-lived, provide a unique window into thermally inaccessible regimes of strong coupling between microscopic degrees of freedom in quantum materials. Understanding the physical origin of…
The way nuclear motion affects electronic responses has become a very hot topic in materials science. Coherent acoustic phonons can dynamically modify optical, magnetic and mechanical properties at ultrasonic frequencies, with promising…
In matter, any spontaneous symmetry breaking induces a phase transition characterized by an order parameter, such as the magnetization vector in ferromagnets, or a macroscopic many-electron wave-function in superconductors. Phase…
Opto-mechanical oscillators that generate coherent acoustic waves are drawing much interest, in both fundamental research and applications. Narrowband oscillations can be obtained through the introduction of feedback to the acoustic wave.…
The mechanism of high-temperature superconductivity in copper oxides (cuprate) remains elusive, with the pseudogap phase considered a potential factor. Recent attention has focused on a long-range symmetry-broken charge-density wave (CDW)…
The temperature-induced orthorhombic to cubic phase transition in Li2C2 is a prototypical example of a solid to solid phase transformation between an ordered phase, which is well described within the phonon theory, and a dynamically…
Important advances have recently been made in the search for materials with complex multi-phase landscapes that host photoinduced metastable collective states with exotic functionalities. In almost all cases so far, the desired phases are…
We investigate spontaneous radiative processes in a driven polar two-level system whose interaction with the laser field is dominated by broken inversion symmetry rather than by the usual transition dipole coupling. Using a polaron…
Molecular hydrogen ions are of metrological relevance due to the possibility of precise theoretical evaluation of their spectrum and of external-field-induced shifts. We report the results of the calculations of the rate of laser-induced…