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Keldysh nonequilibrium Green’s function method; nanowire; temperature dependence; photoinduced current; light emission.

In this paper, we present a theoretical study on a light emitting and current carrying nanosystem, in the nonzero temperature regime. The system under consideration is a semiconducting nanowire sandwiched between two semi-infinite metallic electrodes. The study was performed using the Keldysh nonequilibrium Green’s function method. We systematically investigate the photoinduced current and the light emission induced by this electronic current in the presence of gate voltage. The temperature dependence of these processes are also investigated in the temperature range of 3–300 K. Our study shows that, the photoinduced current is due to the transfer of electrons from highest occupied molecular orbital (HOMO) to the lowest unoccupied molecularorbital (LUMO). Thus, the separation of electron from the electron–hole pair creates a free electron which is responsible for the observed photoinduced current. The same conclusion is also arrived at for the reverse process of light emission under the influence of the electronic current.

Darehdor Mahvash Arabi¹ Shahtahmassebi Nasser¹

1. Department of Physics and Nanocentre Research, Ferdowsi University of Mashhad, Mashhad, Iran

Manuscript received

7 March 2014

Manuscript revised

24 November 2014

Accepted

12 January 2015

Early published

6 October 2015