Ab-initio study of Bulk Photovoltaic effect in Multiferroic Materials

Babu Baijnath Prasad^1,2*, Guang-Yu Guo^1,3

¹Department of Physics, National Taiwan University, Taipei, Taiwan
²Nano Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
³Physics Division, National Center for Theoretical Sciences, Taipei, Taiwan

* Presenter:Babu Baijnath Prasad, email:babubaijnathprasad@gmail.com

The bulk photovoltaic effect (BPVE) has been extensively studied in ferroelectric materials having broken inversion symmetry in past years. However, the study of magnetism-induced photogalvanic currents is still missing in magnetic ferroelectrics BiFeO3 and PbNiO3 which possess large electric polarization of 90 μC/cm2 and 100 μC/cm2 respectively. In this work, we systematically study the linear and circular bulk photovoltaic effect, namely, linear and circular shift and injection current. Our preliminary calculations have shown that the linear shift current conductivity can go up to 72 μA V-2 & -34 μA V-2 whereas it goes as high as -8 μA V-2 & -2 μA V-2 for circular shift current conductivity within the energy range of 0 - 6 eV for multiferroic BiFeO3 and PbNiO3 respectively. Linear injection current susceptibility is 43 × 108 A V-2 s 1 and 6 × 108 A V-2 s 1 for BiFeO3 & PbNiO3 respectively in 0 – 6 eV energy range. Circular injection current susceptibility has a large value of about 21×108 A V-2 s 1 and -66 × 108 A V-2 s 1 for BiFeO3 and PbNiO3 respectively within 0 - 4 eV energy range. Thus, we believe that multiferroic BiFeO3 and PbNiO3 will have promising applications in ferroelectric-based photovoltaic devices.

Keywords: Nonlinear optics, Bulk photovoltaic effect, Multiferroic, Shift current, Injection current