Condensed Matter Seminars

P.W. Anderson envisaged a novel situation of quantum paramagnetic (quantum spin liquid) phase of low spin Mott insulators, back in 1973 and described it using Pauling's  resonating valence bonds states. RVB idea got a resurgence, with the discovery of high Tc superconductivity by Bednorz and Muller in 1986. Low dimensionality and frustrations enhance quantum fluctuations in low spin systems, resulting in a variety of spin liquids and many ideas -  emergent gauge fields, Majorana Fermi sea, to topological phases etc. I will discuss a delightful and exactly solvable model by Kitaev, which realized dreams of RVB theorists and more, in an exact fashion. This fertile model is experimentally realized now, thanks to Khaliullin and Jackeli's prediction. There are continuing surprises, including very recent discovery of anomalous non-linear susceptibility by Shivaram and collaborators.