Study of quantum many-body physics with ultracold atoms

Wednesday 23 Jul 2014, 16:00 → 17:00 Asia/Tokyo

Main Research Bldg. 5F Rom 535 & 537 (RIKEN Wako)

=============================================================================== Pioneer Project Seminar. =============================================================================== Talk Title : Study of quantum many-body physics with ultracold atoms Speaker : Dr.Takeshi Fukuhara Affiliation : RIKEN Center for Emergent Matter Science 　　　　　　 Quantum Many-Body Dynamics Research Unit Unit Leader Schedule : 23rd JULY (Wed) 16:00~, 2014 Place : Main Research Building Room 535 & 537 Language : English Abstract : Ultracold atoms offer unique opportunities to study quantum many-body systems with excellent controllability of their parameters. Especially, atoms loaded into periodic potential (optical lattice) generated by a laser beam can mimic the Hubbard model, where a quantum phase transition occurs from a metallic (superfluid) phase to an insulating phase. In this talk I will present two experimental results with such systems. The first topics is a “Higgs” mode in condensed matter. We observed the Higgs amplitude modes in a two-dimensional superfluid close to the transition point [1], where the system is described by a relativistic field theory. In the second topic, I will talk about quantum dynamics of spin impurities (magnons) in a one-dimensional spin chain comprising atoms in the insulating phase. By tracking the dynamics with high resolution in space and time, we microscopically observed two-magnon bound states [2], which were predicted more than 80 years ago by Hans Bethe, who is also known as a famous nuclear physicist. [1] M. Endres, T. Fukuhara et al., Nature 487, 454 (2012). [2] T. Fukuhara et al., Nature 502, 76 (2013). Contact Yasunori Yamazaki: yasunori _at_ riken.jp (048-467-9482)