Fall 2018

Schedule:

Morning Session Chair: Sergey Frolov, University of Pittsburgh

9:00 Benjamin Hunt, Carnegie Mellon University Tuning Ising Superconductivity with Layer and Spin-Orbit Coupling in 2D Transition-Metal Dichalcogenide Superconductors

9:40 Javad Shabani, New York University Josephson junctions in two-dimensional epitaxial Al-InAs structures

10:20 Coffee Break

10:50 Leonid Glazman, Yale University Demkov-Osherov tunneling of Majorana fermions

11:30 Julia Meyer, CEA Saclay Spontaneous spin polarization of non-equilibrium...

Schedule:

Morning Session Chair: Michael Hatridge, University of Pittsburgh

9:00 Manuel Houzet, CEA Grenoble Microwave spectroscopy of a weakly-pinned charge density wave in a Josephson junction chain

9:40 Erik Bakkers, TU Eindhoven Bottom-up grown nanowire quantum devices

10:20 Coffee Break

10:50 Michel Devoret, Yale University Addressing spectroscopically single Andreev levels in super-semi nanowires

11:30 Peter Krogstrup, Microsoft Quantum and Niels Bohr Institute Hybrid epitaxy of magnetic-semiconductor-superconductor materials...

Schedule:

Morning Session Chair: Victor Vakaryuk, Physical Review

9:00 Chris Palmstrøm, UCSB

9:40 Barbara Jones, IBM. The Keldysh-ETH quantum computation algorithm

10:20 Coffee Break

10:50 Philip Kim, Harvard University. Interlayer Excitons and Magneto-Exciton Condensation in van der Waals Heterostructures

11:30 Andrei Bernevig, Princeton. Topology of Twisted Graphene from Topological Quantum Chemistry

12:10 Lunch Break

Afternoon Session Chair: Benjamin Hunt, Carnegie Mellon University

2:00 Andrea Young, UCSB....

Majorana fermions are non-trivial quantum excitations that have remarkable topological properties and can be used to protect quantum information against decoherence. Tunneling spectroscopy measurements on one-dimensional superconducting hybrid materials have revealed signatures of Majorana fermions which are the edge states of a bulk topological superconducting phase. We couple strong spin-orbit semiconductor InSb nanowires to conventional superconductors (NbTiN, Al) to obtain additional signatures of Majorana fermions and to explore the  topological phase transition. A potent alternative explanation for many of the recent experimental Majorana reports is that a non-topological Andreev state localizes near the end of a nanowire. We compare Andreev and Majorana modes and investigate ways to clearly distinguish the two phenomena. We are also exploring how Andreev states can be chained together along the nanowire to realize the one-dimensional Kitaev model, a discrete way of generating Majorana modes.

A cornerstone of quantum physics is the interference of electron waves arising from the superposition principle. Metallic conductivity is an effect of interference of partial electron waves multiply scattered at the ion cores of the crystal lattice. But proteins are generally insulators. Electron transfer in proteins occurs through either tunneling or hopping a few nanometers via inorganic cofactors. However, the common soil bacteriaGeobacter sulfurreducens transfer electrons over hundreds of micrometers, to insoluble electron acceptors1 or syntrophic partner species2 for...

In principle, quantum computers that exploit the nature of quantum physics can solve some problems much more efficiently than classical computers can.  Motivated by the tremendous scalability of classical silicon electronics, we are working to build a large-scale quantum computer using silicon technology similar to that used to build current classical computers.  This talk will discuss the fundamental physics and materials science challenges that arise, and how close coupling between theory and experiment has enabled substantial progress towards the goal of high fidelity qubits.  Prospects...

Iron-based superconductors are unconventional superconductors with relatively high Tc that derive from metallic parent compounds with several Fe d-states dominant at the Fermi level. This gives rise to a number of novel effects based on differentiated degree of correlation of the different orbital states. I discuss the influence on spin-fluctuation pairing theory of orbital selective strong correlation effects in Fe-based superconductors, particularly Fe chalcogenide systems. This paradigm yields remarkably good agreement with the experimentally observed anisotropic gap structures in both...

Superconducting metamaterials formed from arrays of thin-film lumped circuit elements provide a route for implementing novel dispersion relations and band structure in a circuit QED environment. We have implemented metamaterial resonators from left-handed transmission lines and characterized their dense spectrum of modes through a combination of microwave transmission measurements and laser scanning microscopy imaging of the standing-wave structure on the various resonances. By appending a segment of a conventional transmission line on one end of our metamaterial, we have coupled a flux-...