Eur. Phys. J. B 81, 127-131 (2011)
https://doi.org/10.1140/epjb/e2011-10745-6

Multiple resonances and Coulomb blockade splitting in a quantum dot-DNA composite

¹ Department of Physics and Astronomy, Seoul National University, 151-747 Seoul, Korea
² Department of Physics, Pusan National University, 609-735 Busan, Korea

Corresponding author: ^a jyi@pusan.ac.kr

Received: 28 September 2010
Revised: 9 March 2011
Published online: 13 April 2011

Abstract

Inspired by the recent realizations of quantum dot (QD)-DNA conjugation, we study the spectral density of a magnetic impurity coupled to a mesoscopic semiconducting host. Using a combination of exact diagonalization technique and an analytic approach, we demonstrate that various types of resonances occur according to the relative position of impurity levels (IL) with respect to the host levels (HL). While the usual Coulomb peaks appear when the IL lie inside a band gap, with IL approaching HL and hybridization activated, they shift nonlinearly with the repulsion strength and even undergo splitting for a strong hybridization. When IL merge into HL, multiple resonances of a comblike structure are found along with a parity effect.