Physics Letters A 360 (2006) 1–5 www.elsevier.com/locate/pla Exciton dynamics in a nanocrystal chain with a ring Suc-Kyoung Hong a,b,∗ , Kyu-Hwang Yeon b , Seog Woo Nam a , Shou Zhang c a Department of Display and Semiconductor Physics, Korea University, Seochang, Jochiwon, Chungnam 339-700, South Korea b Department of Physics, College of Natural Science, Chungbuk National University, Cheonju, Chungbuk 361-763, South Korea c Department of Physics, College of Science and Engineering, Yanbian University, Yanji Jilin, 133002, China Received 10 May 2006; received in revised form 29 June 2006; accepted 26 July 2006 Available online 4 August 2006 Communicated by R. Wu Abstract Exciton dynamics in a chain ring consisting of closely spaced nanocrystals has been studied with a simple resonant dipole–dipole interaction model. We show that the electronic excitation population probability, through the resonant energy transport, propagates like a wave packet in the chain and it interferes with itself at each node of the ring. © 2006 Elsevier B.V. All rights reserved. PACS: 73.23.-b; 71.35.-y; 78.90.+t; 72.10.-d Keywords: Nanocrystal chain; Resonant dipole–dipole interaction; Exciton dynamics 1. Introduction The quantum devices such as nanoparticle chain arrays for the control of the excitation in quantum nanostructures [1] have attracted much interests. Recently, much attention has been aroused especially on the study of quantum transport in a nanoparticle array [2,3]. In the studies, specifically, the electronic transport through a quantum dot array containing an arbitrary number of quantum dots connected in series by tunnel coupling has been studied much [4–7]. In addition to the real charge transport by tunnel coupling, quantum trans- port through the electromagnetic energy transfer in a metallic nanoparticle array has also been studied for nanodevices of near field waveguides [1,8]. And the excitation energy transfer via dipole–dipole coupling has been considered for the study of the entanglement of the array [9], as well. The exciton-hopping in a linear array of nanoparticle aggregates is resulted from the en- ergy transfer via resonance dipole–dipole interaction (RDDI). Even though the energy transfer between atoms or molecules in * Corresponding author. E-mail address: sk-hong@korea.ac.kr (S.-K. Hong). solids has been studied enormously, the phenomena of the en- ergy transport in nanostructures have been revived due to the increase of the controlling skill of nanostructures. We are interested in the question of the wave properties of the excitation transport of the nanoparticles. In the process of the excitation-hopping, there has been a consideration on the question of the wavelike feature for the hopping motion of the electronic excitation [10]. For a chain consisting of a ring in it with closely spaced semiconductor nanocrystals, the in- distinguishability of the excitation energy transfer can lead to quantum interference which would enhance the understanding of the energy transfer in an aggregate and the ability to control the interaction between nanoparticles by manipulating the lo- cal quantum environment [2,11,12]. Thus the quantum state of a nano-object can be resolved by analyzing the dependence of energy transfer on the specific configuration of the aggregate. In this work, we are interested in the general feature of the exciton dynamics in a chain consisting of a ring in it with closely spaced semiconductor nanocrystals. In the chain, the electronic excitation population probability, via RDDI, propagates like a wave packet which is reflected and split at a nanoparticle of the ring and finally interferes with itself by combining at a nanoparticle of the other side of the ring. 0375-9601/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.physleta.2006.07.057