Quantum-Mechanical Prediction of Nanoscale Photovoltaics.
Previous simulations of photovoltaic devices are based on classical models, which neglect the atomistic details and quantum-mechanical effects besides the dependence on many empirical parameters. Here, within the nonequilibrium Green's function formalism, we present a quantum-mechanical study of the performance of inorganic nanowire-based photovoltaic devices. On the basis of density-functional tight-binding theory, the method allows simulation of current-voltage characteristics and optical properties of photovoltaic devices without relying on empirical parameters. Numerical studies of silicon nanowire-based devices of realistic sizes with 10 000 atoms are performed, and the results indicate that atomistic details and nonequilibrium conditions have a clear impact on the photoresponse of the devices.
†Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
Yu
Y
Zhang
†Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.|‡Collaborative Innovation Center of Chemistry for Energy Materials, Xiamen University, Xiamen 361005, China.
LingYi
L
Meng
†Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.|§Beijing Computational Science Research Center, No. 3 He-Qing Road, Beijing 100084, China.
ChiYung
C
Yam
†Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
GuanHua
G
Chen
density-functional tight-binding; electron–photon interaction; nonequilibrium Green’s function; photocurrent; silicon nanowire