Related papers: Subpicosecond metamagnetic phase transition driven…
By using intense coherent electromagnetic radiation, it may be possible to manipulate the properties of quantum materials very quickly, or even induce new and potentially useful phases that are absent in equilibrium. For instance, ultrafast…
High-resolution time- and angle-resolved photoemission measurements were made on FeSe superconductors. With ultrafast photoexcitation, two critical excitation fluences that correspond to two ultrafast electronic phase transitions were found…
A model calculation is given for the energy relaxation of a non-equilibrium distribution of hot electrons prepared in a metallic sample that has been subjected to homogeneous photo-excitation by a femtosecond laser pulse. The model assumes…
We present a study of the magnetocaloric effect in metallic systems exhibiting first-order magnetic transitions and focus on consequences of magnetic phase separation. We account for ferrimagnetic, ferromagnetic, and Neel antiferromagnetic…
Ultrafast electron dynamics in solids under strong optical fields has recently found particular attention. In dielectrics and semiconductors, various light-field-driven effects have been explored, such as high-harmonic generation,…
Recent results in electric-field control of magnetism have paved the way for the design of alternative magnetic and spintronic devices with enhanced functionalities and low power consumption. Among the diversity of reported magnetoelectric…
The phase transition to ferromagnetic order in itinerant ferromagnetic superconductor UGe$_2$ as function of pressure shows change of phase transition order. At low temperature and high pressure the transition is of first order and at…
The advent of isolated and intense sub-femtosecond X-ray pulses enables tracking of quantummechanical motion of electrons in molecules and solids. The combination of X-ray spectroscopy and diffraction imaging is a powerful approach to…
We report an unconventional class of pressure induced quantum phase transition, possessing two bicritical points at 6.25 GPa in URhSn. This unique transformation accompanies a Fermi surface reconstruction, demarcating competing ordered…
We report a novel mechanism, consisting of redistribution of valence electrons near the Fermi level, during interactions of intense femtosecond X-ray pulses with a Co/Pd multilayer. The changes in Co 3d valence shell occupation were…
We study the formation of ferromagnetic and magnetic polaron states in weakly doped heterobilayer transition metal dichalcogenides in the ``heavy fermion'' limit in which one layer hosts a dense set of local moments and the other hosts a…
It is a long-standing important issue in heavy fermion physics whether $f$-electrons are itinerant or localized when the magnetic order occurs. Here we report the {\it in situ} scanning tunneling microscopy observation of the electronic…
Ultrafast electron-photon spectroscopy in electron microscopes commonly requires ultrafast laser setups. Photoemission from an engineered electron source is used to generate pulsed electrons, interacting with a sample that is excited by the…
The element specificity of soft X-ray spectroscopy makes it an ideal tool for analyzing the microscopic origin of ultrafast dynamics induced by localized optical excitation in metal-insulator heterostructures. Using [Fe/MgO]$_n$ as a model…
The stabilization of long-range magnetic order in nominally non-magnetic semi-conductors using femtosecond light pulses is an exciting yet experimentally challenging goal. Theoretical studies indicate that certain non-magnetic…
Understanding microscopic processes in materials and devices that can be switched by light requires experimental access to dynamics on nanometer length and femtosecond time scales. Here, we introduce ultrafast dark-field electron…
When a magnetic field confines the carriers of a Fermi sea to their lowest Landau level, electron-electron interactions are expected to play a significant role in determining the electronic ground state. Graphite is known to host a sequence…
The first order antiferromagnetic (AFM) to ferromagnetic (FM) transition in the functional material Fe49(Rh0.93Pd0.07)51 has been studied at low temperatures and high magnetic fields. We have addressed the non-monotonic variation of lower…
The electron motion in atoms and molecules is at the heart of all phenomena in nature that occur outside the nucleus. Recently, ultrafast electron and X-ray imaging tools have been developed to image the ultrafast dynamics of matter in real…
Femtosecond time-resolved second harmonic generation (SHG) measurements were performed at room temperature on a single crystal of LuFe2O4, which has recently attracted attention as an electronic ferroelectric material in which polarization…