10 research outputs found
Magnetic effects in sulfur-decorated graphene
The interaction between two different materials can present novel phenomena that are quite different from the physical properties observed when each material stands alone. Strong electronic correlations, such as magnetism and superconductivity, can be produced as the result of enhanced Coulomb interactions between electrons. Two-dimensional materials are powerful candidates to search for the novel phenomena because of the easiness of arranging them and modifying their properties accordingly. In this work, we report magnetic effects in graphene, a prototypical non-magnetic two-dimensional semi-metal, in the proximity with sulfur, a diamagnetic insulator. In contrast to the well-defined metallic behaviour of clean graphene, an energy gap develops at the Fermi energy for the graphene/sulfur compound with decreasing temperature. This is accompanied by a steep increase of the resistance, a sign change of the slope in the magneto-resistance between high and low fields, and magnetic hysteresis. A possible origin of the observed electronic and magnetic responses is discussed in terms of the onset of low-temperature magnetic ordering. These results provide intriguing insights on the search for novel quantum phases in graphene-based compounds.open1165sciescopu
Recommended from our members
Inductance Investigation of YBa2Cu3O7-δ Nano-Slit SQUIDs Fabricated with a Focused Helium Ion Beam
Focused helium ion beam material modification is ideally suited for the fabrication of YBa2Cu3O7-δ (YBCO) Josephson junctions and superconducting feature sizes down to the nanoscale. We report the fabrication and measurement of YBCO nano-slit SQUIDs and study how scaling the dimensions of the SQUID body and electrodes influences the electrical properties. Sixteen nano-slit SQUIDs with different width and length were fabricated from a single-layer 25-nm-thick YBCO film. The experimental results yield an estimation of the sheet inductance to be ∼4 pH/□ and a penetration depth of ∼180 nm. The temperature dependence of the inductance agree well with an impurity scattering model, indicating that the TC of the film was ∼82 K, and the ratio between geometric inductance and kinetic inductance at 0 K was ∼0.8. These results provide solid basis for the design of high-performance, high-TC micro-SQUID magnetometers
Nano Josephson superconducting tunnel junctions in YBa2Cu3O7–δ directly patterned with a focused helium ion beam
Recommended from our members
YBa2Cu3O7-δ-CeO2-YBa2Cu3O7-δ multilayers grown by reactive co-evaporation on sapphire wafers
High-TC superconductor thin film heterostructures were deposited using reactive co-evaporation for dual layer electronic applications. The epitaxial structure consisted of 35-nm YBa2Cu3O7-δ(YBCO), 75-nm CeO2 , 150-nm YBCO, and 20-nm CeO2 on r-plane sapphire wafers. The critical temperature was measured to be 83.6 K and 84.8 K for the bottom and top YBCO layers, respectively. Atomic force microscopy reveals smooth surfaces with RMS roughness of the top YBCO layer to be 4.7 nm. The CeO2 insulating layer exhibited hopping conduction that freezes out at low temperature, making these structures suitable for electrical circuits with isolated ground planes
Recommended from our members
YBa2Cu3O7-δ-CeO2-YBa2Cu3O7-δ multilayers grown by reactive co-evaporation on sapphire wafers
High-TC superconductor thin film heterostructures were deposited using reactive co-evaporation for dual layer electronic applications. The epitaxial structure consisted of 35-nm YBa2Cu3O7-δ(YBCO), 75-nm CeO2 , 150-nm YBCO, and 20-nm CeO2 on r-plane sapphire wafers. The critical temperature was measured to be 83.6 K and 84.8 K for the bottom and top YBCO layers, respectively. Atomic force microscopy reveals smooth surfaces with RMS roughness of the top YBCO layer to be 4.7 nm. The CeO2 insulating layer exhibited hopping conduction that freezes out at low temperature, making these structures suitable for electrical circuits with isolated ground planes