Lecturer: Prof. Dror Orgad Affiliation: Racah Institute of Physics, The Hebrew University of Jerusalem Abstract: The pseudogap state of the cuprate high- temperature superconductors harbors various fluctuating electronic orders. In particular, recent nuclear magnetic resonance and x-ray scattering measurements have found evidence of charge-density wave (CDW) fluctuations, here, we look to reproduce the experimental phenomenology using a non- linear sigma model of a layered system where superconductivity and CDW orders compete. Using a large-N approximation, and Monte-Carlo simulations, we show that weak inter-layer coupling can stabilize long-range CDW order only in the presence of a magnetic field, which suppresses the superconducting order parameter inside vortex cores. This fact is related to the low temperature behavior of the CDW structure factor, which vanishes linearly with decreasing temperature in the absence of a magnetic field and diverges in its presence. Such behavior is inconsistent with x-ray scattering measurements of underdoped cuprates. On the other hand, qualitative agreement with experiments is obtained when the effect of a random pinning potential is taken into account in our simulations and large-N analysis. Our findings, therefore, point to the importance of disorder in establishing the experimentally observed signatures. ‏האירוע הזה כולל שיחת וידאו ב-Google Hangouts. הצטרף: https://hangouts.google.com/hangouts/_/mail.huji.ac.il/condensed?hceid=b...