Speaker: Mr. Sayak Mandal


Topic: Low dimensional magnetism


Date & Time: Thursday, 14th October 2021 at 4:00 PM



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 Abstract :

 The theory of low-dimensional magnetic systems was first started long back by Ising, Heisenberg and Bethe, though the experimental realisations came at a much later time. Later on, the discovery of high temperature superconductivity in cuprates renewed the interest in understanding the low dimensional magnetic systems. The ground state of an isolated dimer system is a singlet state, whereas the interacting dimers can order antiferromagnetically depending on the ratio of intra and inter dimer exchange interaction strengths. A one-dimensional spin system can show both gapped or gapless excitations with various probable ground states of disordered spin state, spin-Peierls transition and even long-range magnetic ordering. From the singlet ground state of isolated dimers to the gapped/gapless excitation in spin chain to resonating valence bond state in two dimensional systems, the low-dimensional magnetic systems possess a wide range of interesting and exotic magnetic properties. In my seminar, I will be discussing some of the low dimensional magnetic systems and their experimental verifications.

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