120 results match your criteria: "Institute for Quantum Materials and Technologies[Affiliation]"
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January 2025
MEET, Battery Research Center, University of Muenster, 48149, Muenster, Germany.
Rechargeable lithium-ion batteries (LIBs) are critical for enabling sustainable energy storage. The capacity of cathode materials is a major limiting factor in the LIB performance, and doping has emerged as an effective strategy for enhancing the electrochemical properties of nickel-rich layered oxides such as NCM811. In this study, boron is homogeneously incorporated into the tetrahedral site of NCM811 through co-precipitation, leading to an inductive effect on transition metal (TM)-O-B bonds that delayed structural collapse and reduced oxygen release.
View Article and Find Full Text PDFR Soc Open Sci
January 2025
Department of Industrial Chemistry, College of Natural and Applied Sciences, Addis Ababa Science and Technology University, PO Box 16417, Addis Ababa, Ethiopia.
The asymmetric Schiff base prepared from ethylenediamine and pyridine-2-carboxaldehyde reacts with Fe(ClO)·6HO to form the Fe(II) complex [FeL](ClO) with L = ,-diethyl-'-(pyridin-2-yl)methylene)ethane-1,2-diamine, where the Fe(III) starting material has been unexpectedly reduced to Fe(II). This complex was characterized by elemental analysis, infrared spectra, single crystal and powder X-ray diffraction measurements, variable temperature DC magnetic measurement and room temperature Mössbauer spectroscopy. The asymmetric ligand L coordinates in a tridentate fashion through its pyridyl, azomethine and amino nitrogen atoms, generating a distorted octahedral geometry around the central metal ion.
View Article and Find Full Text PDFACS Nano
January 2025
Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe 76131, Germany.
Phys Rev Lett
December 2024
Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, Kaiserstrasse 12, D-76131 Karlsruhe, Germany.
We present a high-resolution single crystal x-ray diffraction study of kagome superconductor CsV_{3}Sb_{5}, exploring its response to variations in pressure and temperature. We discover that at low temperatures, the structural modulations of the electronic superlattice, commonly associated with charge-density-wave order, undergo a transformation around p∼0.7 GPa from the familiar 2×2 pattern to a long-range-ordered modulation at wave vector q=(0,3/8,1/2).
View Article and Find Full Text PDFNanophotonics
November 2024
Chimie ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris, Paris, France.
Efforts to harness quantum hardware relying on quantum mechanical principles have been steadily progressing. The search for novel material platforms that could spur the progress by providing new functionalities for solving the outstanding technological problems is however still active. Any physical property presenting two distinct energy states that can be found in a long-lived superposition state can serve as a quantum bit (qubit), the basic information processing unit in quantum technologies.
View Article and Find Full Text PDFInorg Chem
December 2024
Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe 76131, Germany.
Nat Commun
November 2024
Institute for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen, Germany.
The high-voltage oxygen redox activity of Li-rich layered oxides enables additional capacity beyond conventional transition metal (TM) redox contributions and drives the development of positive electrode active materials in secondary Li-based batteries. However, Li-rich layered oxides often face voltage decay during battery operation. In particular, although Li-rich positive electrode active materials with a high nickel content demonstrate improved voltage stability, they suffer from poor discharge capacity.
View Article and Find Full Text PDFMolecules
October 2024
Université Grenoble Alpes, LNCMI-EMFL, CNRS, INSA-T, and UPS, CEDEX 9, 38042 Grenoble, France.
The longitudinal and transverse nuclear magnetic resonance relaxivity dispersion (NMRD) of H in water induced by the paramagnetic relaxation enhancement (PRE) of dissolved lanthanide ions (Ln) can become very strong. Longitudinal and transverse H NMRD for Gd, Dy, Er and Ho were measured from 20 MHz/0.47 T to 1382 MHz/32.
View Article and Find Full Text PDFChemistry
October 2024
Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Kaiserstr. 12, 76131, Karlsruhe, Germany.
We report the synthesis, structures and magnetic behaviour of two isostructural dinuclear Dy complexes where the metal ions of a previously reported monomeric building block are connected by a peroxide (O ) or a pair of fluoride (2×F) bridges. The nature of the bridge determines the distance between the metal ion dipoles leading to a dipolar coupling in the peroxido bridged compound of only ca. 70 % of that in the bis-fluorido bridged dimer.
View Article and Find Full Text PDFPhys Rev Lett
June 2024
Low Temperature Physics Laboratory, College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing 401331, China.
The unprecedented phenomenon that a charge density wave (CDW) emerges inside the antiferromagnetic (AFM) phase indicates an unusual CDW mechanism associated with magnetism in FeGe. Here, we demonstrate that both the CDW and magnetism of FeGe can be effectively tuned through postgrowth annealing treatments. Instead of the short-range CDW reported earlier, a long-range CDW order is realized below 110 K in single crystals annealed at 320 °C for over 48 h.
View Article and Find Full Text PDFPhys Rev Lett
June 2024
Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
Despite recent experimental developments, the topological order of the fractional quantum Hall state at filling ν=5/2 remains an outstanding question. We study conductance and shot noise in a quantum point contact device in the charge-equilibrated regime and show that, among Pfaffian, particle-hole Praffian, and anti-Pfaffian (aPf) candidate states, the hole-conjugate aPf state is unique in that it can produce a conductance plateau at G=(7/3)e^{2}/h by two fundamentally distinct mechanisms. We demonstrate that these mechanisms can be distinguished by shot noise measurements on the plateaus.
View Article and Find Full Text PDFChem Asian J
November 2024
School of Natural Sciences, Massey University, Private Bag 11 222, Palmerston North, New Zealand.
Sci Adv
June 2024
Institute for Theoretical Condensed Matter Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
Orbital magnetism and the loop currents (LCs) that accompany it have been proposed to emerge in many systems, including cuprates, iridates, and kagome superconductors. In the case of cuprates, LCs have been put forward as the driving force behind the pseudogap, strange-metal behavior, and -wave superconductivity. Here, we investigate whether fluctuating intra-unit-cell LCs can cause unconventional superconductivity.
View Article and Find Full Text PDFNat Commun
June 2024
Department of Physics, Indian Institute of Science, Bangalore, 560012, India.
Collective spin-wave excitations, magnons, are promising quasi-particles for next-generation spintronics devices, including platforms for information transfer. In a quantum Hall ferromagnets, detection of these charge-neutral excitations relies on the conversion of magnons into electrical signals in the form of excess electrons and holes, but if the excess electron and holes are equal, detecting an electrical signal is challenging. In this work, we overcome this shortcoming by measuring the electrical noise generated by magnons.
View Article and Find Full Text PDFPhys Rev Lett
May 2024
Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany.
The kagome materials AV_{3}Sb_{5} (A=K, Rb, Cs) host an intriguing interplay between unconventional superconductivity and charge-density waves. Here, we investigate CsV_{3}Sb_{5} by combining high-resolution thermal-expansion, heat-capacity, and electrical resistance under strain measurements. We directly unveil that the superconducting and charge-ordered states strongly compete, and that this competition is dramatically influenced by tuning the crystallographic c axis.
View Article and Find Full Text PDFNat Commun
May 2024
Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Geschwister-Scholl-Platz 1, 80539, München, Germany.
Indistinguishable single photons in the telecom-bandwidth of optical fibers are indispensable for long-distance quantum communication. Solid-state single photon emitters have achieved excellent performance in key benchmarks, however, the demonstration of indistinguishability at room-temperature remains a major challenge. Here, we report room-temperature photon indistinguishability at telecom wavelengths from individual nanotube defects in a fiber-based microcavity operated in the regime of incoherent good cavity-coupling.
View Article and Find Full Text PDFChemistry
August 2024
Institute of Physical Chemistry (IPC), Karlsruhe Institute of Technology (KIT), Kaiserstr. 12, 76131, Karlsruhe, Germany.
We describe early and recent advances in the fascinating field of combined magnetic and optical properties of inorganic coordination compounds and in particular of 3d-4f single molecule magnets. We cover various applied techniques which allow for the correlation of results obtained in the frequency and time domain in order to highlight the specific properties of these compounds and the future challenges towards multidimensional spectroscopic tools. An important point is to understand the details of the interplay of magnetic and optical properties through performing time-resolved studies in the presence of external fields especially magnetic ones.
View Article and Find Full Text PDFNat Commun
April 2024
Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel.
Despite its ubiquity in quantum computation and quantum information, a universally applicable definition of quantum entanglement remains elusive. The challenge is further accentuated when entanglement is associated with other key themes, e.g.
View Article and Find Full Text PDFNat Commun
April 2024
Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, Kaiserstr. 12, D-76131, Karlsruhe, Germany.
Uniaxial pressure provides an efficient approach to control charge density waves in YBaCuO. It can enhance the correlation volume of ubiquitous short-range two-dimensional charge-density-wave correlations, and induces a long-range three-dimensional charge density wave, otherwise only accessible at large magnetic fields. Here, we use x-ray diffraction to study the strain dependence of these charge density waves and uncover direct evidence for a form of competition between them.
View Article and Find Full Text PDFPhys Rev Lett
March 2024
Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany and Institut für Theorie der Kondensierten Materie, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
A theory of the measurement-induced entanglement phase transition for free-fermion models in d>1 dimensions is developed. The critical point separates a gapless phase with ℓ^{d-1}lnℓ scaling of the second cumulant of the particle number and of the entanglement entropy and an area-law phase with ℓ^{d-1} scaling, where ℓ is a size of the subsystem. The problem is mapped onto an SU(R) replica nonlinear sigma model in d+1 dimensions, with R→1.
View Article and Find Full Text PDFAdv Sci (Weinh)
June 2024
CRISMAT, CNRS, ENSICAEN, UNICAEN, Normandie Univ, Caen, 14000, France.
Due to their amorphous-like ultralow lattice thermal conductivity both below and above the superionic phase transition, crystalline Cu- and Ag-based superionic argyrodites have garnered widespread attention as promising thermoelectric materials. However, despite their intriguing properties, quantifying their lattice thermal conductivities and a comprehensive understanding of the microscopic dynamics that drive these extraordinary properties are still lacking. Here, an integrated experimental and theoretical approach is adopted to reveal the presence of Cu-dominated low-energy optical phonons in the Cu-based argyrodite CuPS.
View Article and Find Full Text PDFJ Am Chem Soc
March 2024
School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China.
Manipulating the chirality of the spin-polarized electronic state is pivotal for understanding many unusual quantum spin phenomena, but it has not been achieved at the single-molecule level. Here, using scanning tunneling microscopy and spectroscopy (STM/STS), we successfully manipulate the chirality of spin distribution in a triple-decker single-molecule magnet tris(phthalocyaninato)bis(terbium(III)) (TbPc), which is evaporated on a Pb(111) substrate via molecular beam epitaxy. The otherwise achiral TbPc becomes chiral after being embedded into the self-assembled monolayer films of bis(phthalocyaninato)terbium(III) (TbPc).
View Article and Find Full Text PDFNat Commun
January 2024
Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, 76049, Germany.
Resistivity measurements are widely exploited to uncover electronic excitations and phase transitions in metallic solids. While single crystals are preferably studied to explore crystalline anisotropies, these usually cancel out in polycrystalline materials. Here we show that in polycrystalline MnZnGeN with non-collinear antiferromagnetic order, changes in the diagonal and, rather unexpected, off-diagonal components of the resistivity tensor occur at low temperatures indicating subtle transitions between magnetic phases of different symmetry.
View Article and Find Full Text PDFInorg Chem
May 2024
Institute of Inorganic Chemistry, Karlsruhe Institute of Technology, Engesserstrasse 15, 76131 Karlsruhe, Germany.
A series of trivalent lanthanide sandwich complexes [(η-CRAs)Ln(η-CH)] using three different arsolyl ligands are reported. The complexes were obtained via salt elimination reactions between potassium arsolyl salts and lanthanide precursors [LnI(COT)(THF)] (Ln = Sm, Dy, Er; COT = η-CH). The resulting compounds exhibit classical sandwich complex structures with one notable exception.
View Article and Find Full Text PDFSci Rep
January 2024
Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), 76344, Eggenstein-Leopoldshafen, Germany.
Polyoxometalates (POM) are anionic oxoclusters of early transition metals that are of great interest for a variety of applications, including the development of sensors and catalysts. A crucial step in the use of POM in functional materials is the production of composites that can be further processed into complex materials, e.g.
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