Kondo Effects with Electrically Neutral Ultracold Atoms

講演日:2019.04.10 (Wed)


後藤 慎平(近畿大学理工学部)


Thanks to recent technical developments in controlling atoms with two outermost electrons and their internal states, analog quantum simulators of multiorbital many-body systems are being realized [1,2]. When quantum simulators are established, a natural next step is simulating some characteristic well-understood physics. In multiorbital many-body systems, the exceptionally well-understood physics is the Kondo effect of the Kondo model: the anomalous temperature dependence of electrical resistivity caused by magnetic impurities [3]. However, ultracold atoms are electrically neutral; How can one measure electrical resistivity?
In this talk, I discuss how to experimentally observe the Kondo effects in ultracold atoms based on our numerical simulations of finite temperature dynamics induced by the sudden shift of trap center. According to the results of our numerical simulations, the center-of-mass velocities, which are measurable in typical experiments, show the anomalous temperature dependence instead of electrical resistivity. The simulations also show that this temperature dependence is absent in the ferromagnetic Kondo model and fully spin-polarized system. These facts strongly indicate that the Kondo effects are detectable by the experimentally measurable center-of-mass velocities.

[1] L. Riegger et al., Phys. Rev. Lett. 120, 143601 (2018).
[2] K. Ono et al., Phys. Rev. A 99, 032707 (2019).
[3] J. Kondo, Prog. Theor. Phys. 32, 37 (1964).