by
Prof.Surjeet Singh(Indian Institute of Science Education and Research, Pune)
→
Asia/Kolkata
AG69
AG69
Description
In this talk, I will show some experimental results concerning the effect
of dilute disorder on the ground state and excitations of quantum spin 1/2
chains. The disorder is induced by doping either magnetic or nonmagnetic
impurity in two representative Heisenberg spin 1/2 chain systems. The
specific results that I will show include: (i) finite-size effects arising
due to spin 0 or spin 1 impurities leading to gapping of the spin
excitations; and (ii) anisotropic spin 1/2 impurities leading to
Heisenberg to Ising crossover.