Condensed Matter Seminar

Gil Refael
CAltech

Thursday, December 11, 2008
1:00 pm in SPL 52

Superfluid-insulator transition in strongly disordered Boson chains: new results from real-space RG

Abstract: The superfluid-insulator transition of bosons has constantly attracted much attention - it describes the physics of Cooper pairs in films and nanowires, as well as Helium and other bosonic atoms. Little is known, however, about this phase transition in the presence of strong disorder. In my talk I will present recent progress in the study of strongly

Using real-space renormalization group, we analyzed the U(1) rotor model with randomness in hopping, charging, and chemical potential, and found the universal low energy properties of the insulating phases in the system. The real-space RG also allows a discussion of the nature and universality of the critical point at large disorder, which we compare to what is known about the superfluid-insulator transition in weakly-disordered bosonic chains.