124 citations · 245 across the 5 of their papers we have counts for
5 papers
Nonlinear optical conductivity of a two-band crystal I
D. J. Passos, G. B. Ventura, J. M. B. Lopes dos Santos +1
The structure of the electronic nonlinear optical conductivity is elucidated in a detailed study of the time-reversal symmetric two-band model. The nonlinear conductivity is decomp…
Second order divergence in the third order DC response of a cold semiconductor
G. B. Ventura, D. J. Passos, J. M. Viana Parente Lopes +1
In this work, we present the analytical expression for the second order divergence in the third order DC response of a cold semiconductor, which can be probed by different electric…
Nonlinear optical responses of crystalline systems: Results from a velocity gauge analysis
D. J. Passos, G. B. Ventura, J. M. Viana Parente Lopes +2
In this work, the difficulties inherent to perturbative calculations in the velocity gauge are addressed. In particular, it is shown how calculations of nonlinear optical responses…
Gauge covariances and nonlinear optical responses
G. B. Ventura, D. J. Passos, J. M. B. Lopes dos Santos +2
The formalism of the reduced density matrix is pursued in both length and velocity gauges of the perturbation to the crystal Hamiltonian. The covariant derivative is introduced as…
On the ferroelectric and magnetoelectric mechanisms in low Fe doped TbMnO
R. Vilarinho, E. Queiros, D. J. Passos +6
This work addresses the effect of substituting Mn by Fe at the octahedral site of TbMnO on the magnetic phase sequence, ferroelectric and magnetoelectric properti…