Related papers: Electric double-layer transistor using layered iro…
In a recent contribution to this journal, it was shown that the transition temperatures of optimal high-Tc compounds obey the algebraic relation, Tc0 = kB-1{\beta}/\ell{\zeta}, where \ell is related to the mean spacing between interacting…
Using one-step solid state reaction method, we have successfully synthesized the superconductor SrFe1-xRuxAs. X-ray diffraction indicates that the material has formed the ThCr2Si2-type structure with a space group I4/mmm. The systematic…
Ferroelectric field-effect transistors employ a ferroelectric material as a gate insulator, the polarization state of which can be detected using the channel conductance of the device. As a result, the devices are of potential to use in…
Among the Fe-based superconductors, Fe$_{1+y}$Te$_{1-x}$Se$_{x}$ is unique in that its crystal structure is the simplest and the electron correlation level is the strongest, and thus it is important to investigate the…
We report the results of electrical and magnetic properties on two new compounds, K0.8Fe1.7S2 and K0.8Fe1.7SeS, both having similar structures to newly discovered superconducting K0.8Fe1.7Se2. K0.8Fe1.7S2 exhibits a semiconductor-like…
We present LDA band structure of novel hole doped high temperature superconductors (Tc~30K) KxFe2Se2 and CsxFe2Se2 and compare it with previously studied electronic structure of isostructural FeAs superconductor BaFe2As2 (Ba122). We show…
2H-NbSe2 is one of the most widely researched transition metal dichalcogenide (TMD) superconductors, which undergoes charge-density wave (CDW) transition at TCDW about 33 K and superconducting transition at Tc of 7.3 K. To explore the…
Electrostatic carrier doping using a field-effect-transistor structure is an intriguing approach to explore electronic phases by critical control of carrier concentration. We demonstrate the reversible control of the insulator-metal…
Superconductivity of high critical temperature ($T_{c}$) superconductors is usually realized through chemical dopant or application of pressure in a similar way to induce charge carriers of either electrons or holes into their parent…
The recently discovered FeAs-based superconductors are a new, promising set of materials for both technological as well as basic research. They offer transition temperatures as high as 55 K as well as essentially isotropic and extremely…
The transition from insulator to superconductor was achieved in the non-superconducting FeSe ultrathin film via simple Mg coating technique in present work. It was found that in non-superconducting FeSe ultrathin film without Mg coating,…
Consecutive topological phase transitions (TPTs) between strongly correlated electronic phases that differ simultaneously in symmetry breaking and topological order are of fundamental interest in condensed matter physics, yet are rarely…
We report an NMR investigation of the superconductivity in BaFe(2)As(2) induced by Co doping (Tc=22K). We demonstrate that Co atoms form an alloy with Fe atoms and donate carriers without creating localized moments. Our finding strongly…
Two-dimensional (2D) transition-metal dichalcogenide (TMDs) MoTe2 has attracted much attention due to its predicted Weyl semimetal (WSM) state and a quantum spin Hall insulator in bulk and monolayer form, respectively. We find that the…
Transition metal dichalcogenides (TMDs) display a rich variety of instabilities such as spin and charge orders, Ising superconductivity and topological properties. Their physical properties can be controlled by doping in electric…
Superconductivity in iron selenides has experienced a rapid growth, but not without major inconsistencies in the reported properties. For alkali-intercalated iron selenides, even the structure of the superconducting phase is a subject of…
In this article we review our studies of the K0.80Fe1.76Se2 superconductor, with an attempt to elucidate the crystal growth details and basic physical properties over a wide range of temperatures and applied magnetic field, including…
FeSe-derived superconductors show some unique behaviors relative to iron-pnictide superconductors, which are very helpful to understand the mechanism of superconductivity in high-Tc iron-based superconductors. The low-energy electronic…
We report quantum oscillation measurements in SrFe2As2 - which is an antiferromagnetic parent of the iron-arsenide family of superconductors - known to become superconducting under doping and the application of pressure. The magnetic field…
Superconducting FeSe0.8Te0.2 thin films on SrTiO3, LaAlO3 and CaF2 substrates were electrochemically etched in an ionic liquid DEME-TFSI electrolyte with a gate bias of 5 V. Superconductivity at 38 K was commonly observed on all substrates…