第4回 物理工学科教室談話会(講師:Dr. Karen Hallberg)

日時: 2015年10月20日(火) 13:30 – 15:00
場所: 工学部6号館3階367,373号室(セミナー室AD)
講師: Dr. Karen Hallberg(Instituto Balseiro and Centro Atomico Bariloche, Bariloche, Argentina)
題目: Quantum phase transition between one-channel and two-channel Kondo polarons

We study the problem of a mobile spin-1/2 impurity, coupled antiferromagnetically to a one-dimensional fermionic gas. Combining general considerations and extensive numerical simulations using DMRG we show that the problem displays a novel quantum phase transition between two-channel and one-channel Kondo screening upon increasing the Kondo coupling. We construct a ground-state phase diagram and discuss the various nontrivial crossovers as well as possible experimental realizations.
紹介教員: 今田正俊教授、求幸年准教授