We report studies of ferroelectricity in ultra-thin perovskite films with realistic electrodes. The results reveal stable ferroelectric states in thin films less than 10 Å thick with polarization normal to the surface. Under short-circuit boundary conditions, the screening effect of realistic electrodes and the influence of real metal/oxide interfaces on thin film polarization are investigated....

Superconducting thin films have the potential to improve the performance of particle accelerators. Before these thin films can be implemented, a systematic study on structureproperty correlations is necessary. Here, we present the characterization of niobium thin films deposited onto both ceramic and metallic substrates. In particular, the film microstructure and superconducting properties are ...

A major problem of current silicon thin film solar cells lies in low carrier collection efficiency due to short carrier diffusion length. Instead of improving the collection efficiency in a relatively thick solar cell, increasing light absorption while still keeping the active layer thin is an alternative solution. Absorption enhancement in a thin film Si solar cell by incorporating a two-dimen...

We study metallic nano-particles for light trapping by investigating the optical absorption efficiency of the hydrogenated amorphous silicon thin film with and without metallic nano-particles on its top. The size and shape of these nano-particles are investigated as to their roles of light trapping: scattering light to the absorption medium and converting light to surface plasmons. The optical ...

The trade-off between transmittance and conductivity of the front contact material poses a bottleneck for thin film solar panels. Normally, the front contact material is a metal oxide and the optimal cell configuration and panel efficiency were determined for various band gap materials, representing Cu(In,Ga)Se₂ (CIGS), CdTe and high band gap perovskites. Supplementing the metal oxide with a me...

The need to obtain information on the performance and lifetime of a tool in service is of prime importance to many industries. It calls for on-line acquisition of information such as temperature and strain values from tools and structures. With embedded sensors, structures are capable of monitoring parameters at critical locations not accessible to ordinary sensors. To embed sensors in the func...

We theoretically show that the three-dimensional (3D) topological insulator (TI)/thin-film ferromagnetic metal (FMM) heterostructure is possible to be a quantum anomalous Hall (QAH) with wide global band gap. Studying structure and weight distributions of eigenstates, we demonstrate attachment metallic thin film on 3DTI can shift topologically nontrivial state into layers due hybridization band...

We show a simple room temperature surface functionalization approach using iodine vapour to control a surface phase transition from cubic silver (Ag) of thin films into wurtzite silver-iodid (β-AgI) films. A combination of surface characterization techniques (optical, electronical and structural characterization) reveal distinct physical properties of the new surface phase. We discuss the AgI t...