Static and Dynamic Control of Topological Matter

Monday, September 30, 2019

Understanding materials based on their underlying topological order has caused a paradigm shift in condensed matter physics in how we classify and describe emergent phenomena in systems. Controlling and engineering these exotic orders is key for next-generation electronics and topological quantum computers. In this talk, I will discuss how the interplay of real and reciprocal space topological order can provide tunable topological phases in a class of multiferroics called the hexagonal manganites[1,2]. Using first-principles calculations and Landau theory, I will describe how the multiferroic orders in these compounds give rise to tunable topological defects and nodal-line semimetals[3,4]. Finally I will discuss how the ultrafast control of topological phases can be achieved by the targeted probing of symmetry-breaking phonons[5].

[1] S.M. Griffin, M. Lilienblum, K.T. Delaney, Y. Kumagai, M. Fiebig and N.A. Spaldin.Phys. Rev. X 2 (4), 041022 (2012)
[2] F.T. Huang, X. Wang, S.M. Griffin, Y. Kumagai, O. Gindele, M.-W. Chu, Y. Horibe, N.A. Spaldin, S.-W. Cheong.Phys. Rev. Lett., 113 (26), 267602 (2014)
[3] Q.N. Meier, M. Lilienblum, S.M. Griffin, K. Conder, E. Pomjakushina, Z. Yan, E. Bourret, D. Meier, F. Lichtenberg, E.K.H. Salje, N.A. Spaldin, M. Fiebig and A. Cano. Phys. Rev. X, 7, 041014 (2017)
[4] S.F. Weber, S.M. Griffin and J.B. Neaton. arXiv:1902.10085 (2019)
[5] S.M. Griffin. To appear in J. Cond. Mat. Phys. (2019)

3 Le Conte Hall
Lawrence Berkeley National Laboratory