Josephson Effect in a Coulomb-blockaded SINIS Junction

The problem of Josephson current through Coulomb-blocked nanoscale superconductor-normal-superconductor structure with tunnel contacts is reconsidered. Two different contributions to the phase-biased supercurrent are identified, which are dominant in the limits of weak and strong Coulomb interaction. Full expression for the free energy valid at arbitrary Coulomb strength is found. The current derived from this free energy interpolates between known results for weak and strong Coulomb interaction as phase bias changes from 0 to pi. In the broad range of Coulomb strength the current-phase relation is substantially non-sinusoidal and qualitatively different from the case of semi-ballistic SNS junctions. Coulomb interaction leads to appearance of a local minimum in the current at some intermediate value of phase difference applied to the junction.Comment: 5 pages, 2 EPS figures, JETP Letters style file include

Correlations of the local density of states in quasi-one-dimensional wires

We report a calculation of the correlation function of the local density of states in a disordered quasi-one-dimensional wire in the unitary symmetry class at a small energy difference. Using an expression from the supersymmetric sigma-model, we obtain the full dependence of the two-point correlation function on the distance between the points. In the limit of zero energy difference, our calculation reproduces the statistics of a single localized wave function. At logarithmically large distances of the order of the Mott scale, we obtain a reentrant behavior similar to that in strictly one-dimensional chains.Comment: Published version. Minor technical and notational improvements. 16 pages, 1 figur

Up against a Wall: Europe’s Options for Regulating Biotechnology through Regulatory Anarchy

Based on the current state of EU law and the political sentiment surrounding Genetically Modified Organisms, this paper argues that the best approach to regulating the import and export of GMOs into the Community and between Member States is by what I will call for the purposes of this Paper “regulatory anarchy.” This system sits in opposition to a hierarchical regulatory approach which may be associated with traditional neo-functionalist theories of Community integration. Applied in the context of GMOs, regulatory anarchy envisions integration not coming solely from Community rules conceived by the Commission, but by Member State negotiated rules accomplished at the level of regulatory civil servants negotiating among each other. Greater centralization will occur in the regulation of GMOs because the risk of defection in this area by an individual regulatory body imposes very high costs on other national regulators, to the point where they are willing to relinquish some of their own enforcement authority for assurances against collective action problems. Due to the current gridlock caused by recalcitrant Member States, the GMO regime may be more effectively and efficiently handled by a system that employs regulatory anarchy; whereby twenty-five interested parties are initially brought to the table to approve a release (rather than one Member State), leaving less opportunities for regulatory capture by one Member State and still leaving room for Community supervision