A5061888132- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- 2D Materials and Applications
- Magnetic and transport properties of perovskites and related materials
- Fullerene Chemistry and Applications
- MXene and MAX Phase Materials
- Organic and Molecular Conductors Research
- Graphene research and applications
- Molecular Junctions and Nanostructures
- Electronic and Structural Properties of Oxides
- Iron-based superconductors research
- Advanced Chemical Physics Studies
- Magnetic properties of thin films
- Diamond and Carbon-based Materials Research
- Perovskite Materials and Applications
- Advanced Memory and Neural Computing
- Inorganic Chemistry and Materials
- High-pressure geophysics and materials
- Carbon Nanotubes in Composites
- Superconductivity in MgB2 and Alloys
- Quantum and electron transport phenomena
- Inorganic Fluorides and Related Compounds
- Transition Metal Oxide Nanomaterials
- Rare-earth and actinide compounds
- Spectroscopy and Quantum Chemical Studies
Jožef Stefan Institute
2015-2024
Nanocenter
2015-2024
University of Ljubljana
2015-2024
Institute of Mathematics, Physics, and Mechanics
2003-2023
Jožef Stefan International Postgraduate School
2006-2022
University of Nis
2011-2021
Hokkaido University
2021
Radboud University Nijmegen
2019
TU Dortmund University
2019
SLAC National Accelerator Laboratory
2017
Exposing a Hidden State Shining intense laser light on material can temporarily alter its properties. The effect usually subsides after few picoseconds, unless the system is trapped in metastable state, which case transient period may last as long microseconds. Stojchevska et al. (p. 177 ) observed that, following exposure to 35-femtosecond pulse, layered dichalcogenide 1T -TaS 2 entered stable “hidden” state not present equilibrium phase diagram and stayed there indefinitely. switch hidden...
We report on the synthesis, structure, and self-assembly of single-wall subnanometer-diameter molybdenum disulfide tubes. The nanotubes are up to hundreds micrometers long display diverse properties different length scales, ranging from twisted bundles regularly shaped “furry” forms. bundles, which contain interstitial iodine, can be readily disassembled into individual nanotubes. synthesis was performed using a novel type catalyzed transport reaction including C 60 as growth promoter.
Abstract Terahertz (THz) radiation encompasses a wide spectral range within the electromagnetic spectrum that extends from microwaves to far infrared (100 GHz–∼30 THz). Within its frequency boundaries exist broad variety of scientific disciplines have presented, and continue present, technical challenges researchers. During past 50 years, for instance, demands community substantially evolved with need advanced instrumentation support radio astronomy, Earth observation, weather forecasting,...
In the last two decades non-equilibrium spectroscopies have evolved from avant-garde studies to crucial tools for expanding our understanding of physics strongly correlated materials. The possibility obtaining simultaneously spectroscopic and temporal information has led insights that are complementary (and in several cases beyond) those attainable by studying matter at equilibrium. From this perspective, multiple phase transitions new orders arising competing interactions benchmark examples...
Abstract The functionality of computer memory elements is currently based on multi-stability, driven either by locally manipulating the density electrons in transistors or switching magnetic ferroelectric order. Another possibility between metallic and insulating phases motion ions, but their speed limited slow nucleation inhomogeneous percolative growth. Here we demonstrate fast resistance a charge wave system caused pulsed current injection. As pulse travels through material, it converts...
Photoexcited quasiparticle relaxation dynamics are investigated in a ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ superconductor as function of doping \ensuremath{\delta} and temperature $T$ using ultrafast time-resolved optical spectroscopy. A model calculation is presented that describes the dependence photoinduced population ${n}_{\mathrm{pe}},$ transmission $\ensuremath{\Delta}\mathcal{T}/\mathcal{T},$ time \ensuremath{\tau} for...
The low-energy electronic excitation spectrum and gap structure in optimally doped overdoped Y_{1-x}Ca_{x}Ba_{2}Cu_{3}O_{7-\delta} single crystals are investigated by real-time measurements of the quasiparticle relaxation dynamics with femtosecond optical spectroscopy. From amplitude photoinduced reflectivity as a function time, temperature doping x we find clear evidence for coexistence two distinct gaps entire phase. One is temperature-independent pseudogap $\Delta_{p}$ other T-dependent...
Ultrafast transient reflectivity changes caused by collective and single particle excitations in the quasi one-dimensional charge-density wave (CDW) semiconductor K0.3MoO3 are investigated with optical pump-probe spectroscopy. The temperature-dependence of non-equilibrium across CDW gap their recombination dynamics reported for first time. In addition, amplitude mode oscillations observed real A T-dependent overdamped response is also which attributed to relaxation phason mode.
Large amounts of Li ions can be electrochemically intercalated into and controllably released by the channels between individual molybdenum selenide nanotubes (see Figure), forming basis for a promising safe new battery electrode material. The use dichalcogenide rather than more usual carbon is shown to have important advantages.
We analyze the frequency-dependent photoinduced infrared conductivity, ${\mathrm{\ensuremath{\sigma}}}_{\mathit{P}}$(\ensuremath{\omega}), obtained from absorption measurements of insulators ${\mathrm{Tl}}_{2}$${\mathrm{Ba}}_{2}$${\mathrm{Ca}}_{0.98}$${\mathrm{Gd}}_{0.02}$${\mathrm{Cu}}_{2}$${\mathrm{O}}_{8}$, ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{6.3}$, and ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$ in terms ${\mathrm{\ensuremath{\sigma}}}_{\mathrm{PT}}$(\ensuremath{\omega})...
We determined electronic relaxation times via pump-probe optical spectroscopy using sub-15 fs pulses for the normal state of two different cuprate superconductors. show that primary process is electron-phonon interaction and extract a measure its strength, second moment Eliashberg function λ[ω2] = 800 ± 200 meV2 La(1.85)Sr(0.15)CuO4 400 100 YBa(2)Cu(3)O(6.5). These values suggest possible fundamental role in superconducting pairing mechanism.
Revealing the relaxation mechanisms of hidden states in transition metal dichalcogenides leads to control metastability.
Femtosecond time-resolved spectrocopy has been used to investigate electronic excitations contributing the superconducting gap function $\ensuremath{\Delta}(\ensuremath{\omega},T)$ in ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$. The optical response is strongly peaked at 1.5 eV, and contains two distinct components: one with a characteristic relaxation time of $\ensuremath{\sim}5\mathrm{ps}$, whose amplitude displays two-fluid-like temperature...
Superconducting state dynamics following excitation of a superconductor with femtosecond optical pulse is studied in terms phenomenological Rothwarf and Taylor model. Analytical solutions for various limiting cases are obtained. The model found to account the intensity temperature dependence both photoinduced quasiparticle density, as well pair-breaking superconducting recovery conventional cuprate superconductors.
We have studied the vibrational and electronic structure elementary charged excitations of poly(1,4-phenylene-vinylene) a series its (2,5-alkoxy) derivatives including poly(2,5-methoxy-PV), poly(2,5-hexoxy-PV), poly(2,5-octoxy-PV), poly[2-methoxy,5-(2'ethyl-hexoxy)-PV] by absorption, photoinduced (PI) doping-induced (DI) absorption. For pristine materials, we observe that band gap decreases as much \ensuremath{\sim}0.3 eV with introduction alkoxy side chains. assign observed ir-active...
We use ultrashort intense laser pulses to study superconducting state vaporization dynamics in La2-xSrxCuO4 (x=0.1 and 0.15) on the femtosecond time scale. find that energy density required vaporize is 2.0+/-0.8 2.6+/-1.0 K/Cu for x=0.1 0.15, respectively. This significantly greater than condensation density, indicating quasiparticles share a large amount of with boson glue bath this Considering detail both spin lattice relaxation pathways which take place relevant scale approximately...
The 2D semiconductor MoS 2 in its mono‐ and few‐layer form is expected to have a significant exciton binding energy of several 100 meV, suggesting excitons as the primary photoexcited species. Nevertheless, even single layers show strong photovoltaic effect work active material high sensitivity photodetectors, thus indicating efficient charge carrier photogeneration. Here, modulation spectroscopy sub‐ps ms time scales used study photoexcitation dynamics . results suggest that...
We present, for the first time to our knowledge, WS<sub>2</sub> photoexcited state dynamics and propose a model that reproduces them.