Eur. Phys. J. D (2014) 68: 361
https://doi.org/10.1140/epjd/e2014-50332-y

Regular Article

Interacting heavy fermions in a disordered optical lattice

¹ Key Laboratory for Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, P.R. China
² University of Chinese Academy of Sciences, Beijing 100049, P.R. China
³ State Key Laboratory of Precision Measurement, East China Normal University, Shanghai 200241, P.R. China
⁴ State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, P.R. China

^a e-mail: jqian@mail.siom.ac.cn
^b e-mail: dujuan@mail.siom.ac.cn
^c e-mail: yzwang@mail.shcnc.ac.cn

Received: 26 December 2013
Received in final form: 22 August 2014
Published online: 2 December 2014

Abstract

We have theoretically studied the effect of disorder on ultracold alkaline-earth atoms governed by the Kondo lattice model in an optical lattice via simplified double-well model and hybridization mean-field theory. Disorder-induced narrowing and even complete closure of hybridization gap have been predicted and the compressibility of the system has also been investigated for metallic and Kondo insulator phases in the presence of the disordered potential. To make connection to the experimental situation, we have numerically solved the disordered Kondo lattice model with an external harmonic trap and shown both the melting of Kondo insulator plateau and a compressibility anomaly at low-density.