Kinetics and Entanglement in Quantum Devices

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

NONTECHNICAL SUMMARY This award supports research and education on time-dependent phenomena in nanodevices, such as the transfer of heat and charge. Recent progress in information technology has greatly exceeded even the wildest dreams of science fiction writers of the sixties and the seventies. The cornerstone of this still unfolding revolution has been the exhaustive theoretical understanding of semiconductor materials. Based entirely on quantum mechanics, it has enabled technology to manufacture and pack billions of transistors per square centimeter. The next big frontier in this quest is building a quantum computer, which will enable calculation capacity infeasible in current classical devices. As before, the crucial step is in imagining, predicting, and eventually finding materials with the proper "quantum pedigree" that will be up to the task. Most experts agree that we already have a perfect candidate for the job, the so-called topological insulators. These novel compounds have unique electronic properties that make them ideal for the processing and storage of quantum information. The proposed activity will advance the theoretical understanding of these materials and expand on the ways they can be employed in quantum computation. The award will also support graduate students and a postdoctoral researcher, which will be trained in modern theoretical and computational techniques, and will have opportunities to visit and interact with experimentalists. The results of the research will be published in scientific journals, and will be presented in national and international conferences. The PI will co-organize a two-week summer school at the University of Minnesota, and a public lecture series in theoretical physics that is attended by more than 500 members of the Twin-Cities community. TECHNICAL SUMMARY This award supports research and education on nonequilibrium dynamics and entanglement propagation in quantum devices. Topological properties of electronic spectra, which play increasingly prominent role in these structures, lead to transitions between various topologically distinct phases. Disorder, inevitably present in any realistic device, qualitatively changes electron dynamics in the vicinity of such quantum phase transitions (QPT). The activity will focus on: (i) investigating heat and charge transfer in the vicinity of a topological QPT and developing concrete experimental setups that will be capable to probe such near-critical dynamics, (ii) investigating finite-size and dynamical scaling for various measures of quantum entanglement across a QPT, (iii) investigating hidden topological characteristics of quasicrystals, (iv) aiding and advancing experimental efforts in the search for neutral edge modes of fractional quantum Hall structures and in the characterization of superconducting nanowires, (v) advancing a theory of dissipative quantum tunneling in molecular magnets. The award will also support graduate students and a postdoctoral researcher, which will be trained in modern theoretical and computational techniques, and will have opportunities to visit and interact with experimentalists. The results of the research will be published in scientific journals, and will be presented in national and international conferences. The PI will co-organize a two-week summer school at the University of Minnesota, and a public lecture series in theoretical physics that is attended by more than 500 members of the Twin-Cities community.