Research highlights

  • superconducting computer memory

We report a superconducting kinetic inductance memory (SKIM) element, which can be controlled exclusively by the bias supercurrent, without involving magnetic fields and heating elements. The kinetic inductance is provided by extremely narrow nanowires or nanobridges. The SKIM is a nonvolatile memory. The device is made of two Nb Dayem bridges, and it can operate reliably up to 2.8 K. The achieved error rate is as low as one in 105. The memory element could find applications in superconducting supercomputers.

  • Research

Article abstract: We derive the general analytical solution of the viscous hydrodynamic equations for an ultrarelativistic gas of hard spheres undergoing Bjorken expansion, taking into account effects from particle number conservation, and use it to analytically determine its attractor at late times. Differently than all the cases considered before involving rapidly expanding fluids, in this example the gradient expansion converges. We exactly determine the hydrodynamic attractor of this system when its microscopic dynamics is modeled by the Boltzmann equation with a fully nonlinear collision kernel. The exact late time attractor of this system can be reasonably described by hydrodynamics even when the gradients are large.