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Within the field of solid-state physics, the discovery of remarkable phases and transitions is often tightly coupled to the design, growth and characterization of novel materials. Therefore, the past several decades of work in the field of correlated electron physics can be described by a list of materials that have defined new states of matter at extreme conditions, e.g. low temperatures, high magnetic field or pressure. In most cases, a thorough understanding of the underlying physical mechanisms is accessible only, if high-quality single crystals with sufficient sizes are available. In this lecture, I shall give an overview about my own contributions to this research area in recent years focusing on three very different material classes (i) quantum criticality and superconductivity in heavy-fermion metals [1-3], (ii) crystal growth of LnFeAsO iron-pnictide superconductors [4,5], and (iii) spin-liquid phases in Cu-based frustrated spin systems [6]. References [1] A. Steppke et al., Science 339, 933 (2013). [2] E. Schuberth et al., Science 351, 6272 (2016). [3] H. Pfau et al., Phys. Rev. Lett. 119, 126402 (2017). [4] A. Jesche et al., Phys. Rev. B 86, 020501(R) (2012). [5] A. Adamski et al., Phys. Rev. B 96, 100503(R) (2017). [6] P. Puphal et al., J. Mater. Chem. C 5, 2629 (2017).

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Cornelius Krellner, Universität Frankfurt
Seminar Room of the Institute of Physics 2
Contact: M. Braden