Multiferroics are materials where two or more ferroic orders coexist owing to the interplay
between spin, charge, lattice and orbital degrees of freedom. The explosive expansion of …

In this paper, using a resonance-enhanced piezoresponse force microscopy approach
supported by density functional theory computer simulations, we have demonstrated the …

Nonlinear optics is an important and exciting field of fundamental and applied research, with
applications in many different disciplines such as physics chemistry, material science and …

Calculations of the second-harmonic susceptibility tensor χ abc (− 2 ω; ω, ω) are presented
for bulk semiconductors within both the v⋅ A and the r⋅ E gauges. The description of the …

Surface optical and electronic properties are crucial for material science and have
implications in fields as various as nanotechnology, nonlinear optics, and spectroscopies. In …

The electronic properties of Ga-doped ZnO with wurtzite structures are studied using the
frozen-core projector augmented wave method based upon the density functional theory …

We present a critical analysis of the procedures and approximations which are generally
used to obtain the optical properties of a real solid surface starting from microscopic …

We formulate a theoretical approach of surface second-harmonic generation from
semiconductor surfaces based on the length gauge and the electron density operator. Within …

The theory and practice of the non-linear optics of silicon are inextricably linked with a
variety of areas of solid state physics, particularly semiconductor physics. However, the …

The optically induced electron dynamics at a Si (001) surface is studied using a five-wave-
mixing setup which measures the diffracted second-harmonic intensity induced by three …