arXiv 0807.06672008-07-04cond-mat.mes-hall

Intense Terahertz Laser Fields Induced and Manipulated Pseudospin Polarization in Graphene

J. Zhou

备注：: 4 pages, 4 figures

英文摘要：

We investigate the pseudospin-dependent density-energy relation (whose differential with respect to energy is density of states) of a monolayer graphene under intense terahertz laser field by exactly solving the time-dependent Schrödinger equation with help of Floquet's theorem. We find that psedospin polarization can be induced by a circular polarized terahertz laser field. The psedospin polarization in K and K$^{\prime}$ valleys can be exactly opposite sign when the electron densities in these two calleys are equivalent. Further more, we find that the psedospin polarization can be manipulated by the strength, frequency, and especially the polarization orientation of the field.

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