• Tortech, L.
• Barrett, N.
• Mathieu, C.
• Renault, O.
• Rhun, G. Le
• Copie, O.
• Vilquin, Bertrand

Abstract

The ferroelectric control of the electronic properties of topological or surface states is a very promising approach for future electronic applications such as in spintronics. Recently, first principle calculations have predicted that bismuth (Bi) spin Rashba splitting can be manipulated by the spontaneous electronic polarization of a ferroelectric material [1]. The purpose of our work is thus to determine directly the effect of the electric polarization of written ferroelectric domains on the Rashba spin splitting of a thin Bi layer using spatially resolved photoemission spectroscopy. Towards this goal, on the one hand, ferrolectric domains were polarized in (Pb,Zr)TiO3 thin film using piezoresponse force microscopy (PFM). Then, we have characterized these domains using energy filtered photoelectron emission microscopy (PEEM) and low energy electron microscopy (LEEM). On the other hand, we have optimized and characterized the growth of Bi by e-beam evaporation on an oxide substrate. Finally, we performed PEEM experiments in the momentum space to measure the electronic band structure of the Bi thin film deposited on the oxide substrate and the ferroelectric material. This approach will show the control of electronic properties, while measuring in situ the band structure by photoemission spectroscopy, and it will illustrate the direct response of electric manipulation of the spin degree of freedom for spintronics application. [1] H. Mirhosseini et al., PRB 81, 073406 (2010).

Topics

• impedance spectroscopy
• surface
• experiment
• thin film
• electron microscopy
• evaporation
• band structure
• Bismuth