Mott-Superfluid Transition for Spin-Orbit Coupled Bosons in One-Dimensional Optical Lattices

We study the effects of spin-orbit coupling on the Mott-superfluid transition of bosons in a one-dimensional optical lattice. We determine the strong coupling magnetic phase diagram by a combination of exact analytic and numerical means. Smooth evolution of the magnetic structure into the superfluid phases are investigated with the density matrix renormalization group technique. Novel magnetic phases are uncovered and phase transitions between them within the superfluid regime are discussed. Possible experimental detection are discussed.Comment: 5 pages, 4 figure

Direct investment: a doubtful alternative to international debt

The paper considers a model in which private foreign investors make direct long-lived capital investments in a small developing country that is subject to stochastic shocks to production. Depending upon the preferences of the host country, we find that expropriation can occur because of either desperation or opportunism. We show that under reasonable assumptions, increased investment makes expropriation less likely to occur and that the level of investment chosen by atomistic foreign investors may be nonoptimal.International finance ; Developing countries

Effects of large induced superconducting gap on semiconductor Majorana nanowires

With the recent achievement of extremely high-quality epitaxial interfaces between InAs nanowires and superconducting Al shells with strong superconductor-semiconductor tunnel coupling, a new regime of proximity-induced superconductivity in semiconductors can be explored where the induced gap may be similar in value to the bulk Al gap (large gap) with negligible subgap conductance (hard gap). We propose several experimentally relevant consequences of this large-gap strong-coupling regime for tunneling experiments, and we comment on the prospects of this regime for topological superconductivity. In particular, we show that the advantages of having a strong spin-orbit coupling and a large spin g-factor in the semiconductor nanowire may both be compromised in this strongly coupled limit, and somewhat weaker interface tunneling may be necessary for achieving optimal proximity superconductivity in the semiconductor nanowire. We derive a minimal, generic theory for the strong-coupling hard-gap regime obtaining good qualitative agreement with the experiment and pointing out future directions for further progress toward Majorana nanowires in hybrid semiconductor-superconductor structures.Comment: 8 pages, 5 figures; published versio

Solar PhotoVoltaic

The New Hampshire National Guard Training Site located in Strafford, New Hampshire plans to utilize renewable energy to meet the goal of becoming a net zero facility by 2030 for electrical consumption in accordance with the American Institute of Architects 2030 net zero initiative. In order to be considered a net zero facility, all energy consumed would have to be offset by energy supplied by renewable sources. William selected this project because it had some really good lessons learned early on in the project that really helped shape his view of his role as a project manager. Williams’s major takeaway from this project is that communication is king. There was some rough going early on in the project but once the team ironed out their communication things really turned around and the project hit all the milestones and finished on time