Zobrazeno 1 - 10
of 346
pro vyhledávání: '"Passos D"'
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 decomposed as a sum of contributions related with different regions of the F
Externí odkaz:
http://arxiv.org/abs/2102.07629
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 field setups. Results from this expression were then compared, for th
Externí odkaz:
http://arxiv.org/abs/2004.01919
In this work, we present numerical results for the second and third order conductivities of the plain graphene and gapped graphene monolayers associated with the second and third harmonic generation, the optical rectification and the optical Kerr eff
Externí odkaz:
http://arxiv.org/abs/1902.04438
Autor:
Passos, D. J., Ventura, G. B., Lopes, J. M. Viana Parente, Santos, J. M. B. Lopes dos, Peres, N. M. R.
Publikováno v:
Phys. Rev. B 97, 235446 (2018)
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 in the independent particle approximation can be done to any order an
Externí odkaz:
http://arxiv.org/abs/1712.04924
Autor:
Ventura, G. B., Passos, D. J., Santos, J. M. B. Lopes dos, Lopes, J. M. Viana Parente, Peres, N. M . R.
Publikováno v:
Phys. Rev. B 96, 035431 (2017)
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 a convenient representation of the position operator. This allow us to
Externí odkaz:
http://arxiv.org/abs/1703.07796
Publikováno v:
A&A 607, A120 (2017)
Surface observations indicate that the speed of the solar meridional circulation in the photosphere varies in anti-phase with the solar cycle. The current explanation for the source of this variation is that inflows into active regions alter the glob
Externí odkaz:
http://arxiv.org/abs/1702.02421
Autor:
Vilarinho, R., Queiros, E., Passos, D. J., Mota, D. A., Tavares, P. B., Mihalik jr., M., Zentkova, M., Mihalik, M., Almeida, A., Moreira, J. Agostinho
Publikováno v:
Journal of Magnetism and Magnetic Materials 439, 167-172 (2017)
This work addresses the effect of substituting Mn$^{3+}$ by Fe$^{3+}$ at the octahedral site of TbMnO$_3$ on the magnetic phase sequence, ferroelectric and magnetoelectric properties, keeping the Fe$^{3+}$ concentration below 5%. The temperature depe
Externí odkaz:
http://arxiv.org/abs/1602.01574
Publikováno v:
SciPost Physics Proceedings, Iss 11, p 021 (2023)
SmCo$_5$ and YCo$_5$ are isostructural compounds both showing large magnetocrystalline anisotropy, where the former originates mainly from the crystal-electric field and magnetic interactions. We investigate the contribution of both interactions by p
Externí odkaz:
https://doaj.org/article/9fb1c93d33a24cf9ae84ac48ebb57180
Autor:
Chisini, L. A., Boeira, G. F., Corrêa, M. B., Salas, M. M. S., Maciel, F. V., Passos, D., Gigante, D., Opdam, N., Demarco, F. F.
Publikováno v:
European Archives of Paediatric Dentistry (Springer Science & Business Media B.V.); Jun2024, Vol. 25 Issue 3, p335-347, 13p
Publikováno v:
A&A 563, A18 (2014)
Extreme solar activity fluctuations and the occurrence of solar grand minima and maxima episodes, are well established, observed features of the solar cycle. Nevertheless, such extreme activity fluctuations and the dynamics of the solar cycle during
Externí odkaz:
http://arxiv.org/abs/1309.2186