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A high temperature superconducting detector was fabricated to capture the thermal images in room temperature background. The detector was made of YBa2Cu3O7-{\delta} (YBCO) superconducting thin film deposited on an Yttria Stabilized Zirconia (YSZ) substrate, structurally modified for high responsivity performance. A very thin absorber layer was implemented on the backside of the detector to increase the absorption of the device at infrared (IR) range of frequencies. To capture thermal images, a movable off-axis parabolic mirror on XY plane was used for focusing the incoming IR radiation including the thermal signal of the objects onto the device surface. The captured thermal images belong to the objects within the temperature range between 300K and 400K, which correspond to our imaging optics., Comment: Will be submitted in "superconductor science and technology" journal

We present triple-axis neutron scattering studies of static and dynamic magnetic stripes in an optimally oxygen-doped cuprate superconductor, La$_{2}$CuO$_{4+y}$, which exhibits a clean superconducting transition at $T_{\rm c}=42$ K. Polarization analysis reveals that the magnetic stripe structure is equally represented along both of the tetragonal crystal axes and that the fluctuating stripes display significant weight for in-plane as well as out-of-plane spin components. Both static magnetic order as well as low-energy fluctuations are fully developed in zero applied magnetic field and the low-energy spin fluctuations at $\hbar \omega = 0.3-10$ meV intensify upon cooling. We interpret this as an indication that superconductivity and low-energy spin fluctuations co-exist microscopically in spatial regions which are separated from domains with static magnetic order., Comment: 16 pages, 6 figures

Inelastic neutron scattering has been used to study the in-plane Cu-O bond-stretching mode in oxygendoped La1.94Sr0.06CuO4.035 (T-c = 38 K) and La2CuO4+delta (T-c = 43 K). Similar to results from optimally doped La1.85Sr0.15CuO4 (T-c = 35 K), we observe anomalous features in the dispersion of this half-breathing mode in the form of a softening halfway through the Brillouin zone. Considering the differences in electronic structure and local environment between the oxygen- and strontium-doped compounds with similar T-c, we rule out a connection between the phonon anomaly and structural instabilities related to the specific dopant type. We interpret the phonon anomaly as a signature of correlated charge fluctuations ubiquitous in optimally doped superconductors.

Inelastic neutron scattering has been used to study the in-plane Cu-O bond-stretching mode in oxygen doped La$_{1.94}$Sr$_{0.06}$CuO$_{4.035}$ ($T_c = 38\,\text{K}$) and La$_2$CuO$_{4+\delta}$ ($T_c = 43\,\text{K}$). Similar to results from optimally doped La$_{1.85}$Sr$_{0.15}$CuO$_4$ ($T_c = 35\,\text{K}$), we observe anomalous features in the dispersion of this half-breathing mode in the form of a softening halfway through the Brillouin Zone. Considering the differences in electronic structure and local environment between the oxygen- and strontium-doped compounds with similar $T_\text{c}$, we rule out a connection between the phonon anomaly and structural instabilities related to the specific dopant type. We interpret the phonon anomaly as a signature of correlated charge fluctuations possibly connected to stripes., Comment: 6 pages, 4 figures, Supplemental Material

Inelastic neutron scattering has been used to study the in-plane Cu-O bond-stretching mode in oxygen doped La$_{1.94}$Sr$_{0.06}$CuO$_{4.035}$ ($T_c = 38\,\text{K}$) and La$_2$CuO$_{4+��}$ ($T_c = 43\,\text{K}$). Similar to results from optimally doped La$_{1.85}$Sr$_{0.15}$CuO$_4$ ($T_c = 35\,\text{K}$), we observe anomalous features in the dispersion of this half-breathing mode in the form of a softening halfway through the Brillouin Zone. Considering the differences in electronic structure and local environment between the oxygen- and strontium-doped compounds with similar $T_\text{c}$, we rule out a connection between the phonon anomaly and structural instabilities related to the specific dopant type. We interpret the phonon anomaly as a signature of correlated charge fluctuations possibly connected to stripes., 6 pages, 4 figures, Supplemental Material