Regular Article

Beneficial impact of a thin tunnel barrier in quantum well intermediate-band solar cell

¹ Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille, France
² NextPV, LIA, CNRS-RCAST/U, Tokyo-U, Bordeaux, Tokyo 153-8904, Japan
³ Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo 153-8904, Japan
⁴ LIMMS, CNRS-Institute of Industrial Science, UMI 2820, University of Tokyo, Tokyo 153-8505, Japan
⁵ IRDEP, UMR 7174 CNRS EDF Chimie ParisTech, EDF R&D, Chatou, France

^* e-mail: nicolas.cavassilas@im2np.fr

Received: 25 July 2018
Received in final form: 16 October 2018
Accepted: 19 October 2018
Published online: 30 November 2018

Abstract

Based on electronic quantum transport modeling, we study the transition between the intermediate-band and the conduction-band in nano-structured intermediate-band solar cell. We show that a tunnel barrier between the quantum well (QW) and the host material could improve the current. The confinement generated by such a barrier favors the inter-subband optical coupling in the QW and then changes the excitation-collection trade-off. More surprisingly, we also show that tunneling impacts the radiative recombination and then the voltage. Using a detailed balance model we explain and we propose a broadening factor for this V_oc modification. Finally we show that a thin tunnel barrier is beneficial for both current and voltage.