I.M. Moiseenko1, V.V. Popov2, D.V. Fateev3

1−3 Kotelnikov IRE of RAS, Saratov Branch (Saratov, Russia)

Problem formulating. Currently, there are no compact, efficient terahertz radiation sources operating at room temperature. To create such sources and amplifiers, structures based on graphene with DC-current can be used. 

Goal. Finding conditions for achieving the negative real part of graphene conductivity and amplification of THz radiation in graphene with a direct electric current.

Result. It is shown that for a certain value of direct electric current in graphene, the reflection coefficient of the THz wave incident on the structure based on graphene with DC-current exceeds unity, which indicates the amplification of THz radiation in the structure. The amplification of the THz radiation in graphene is achieved due to negative values of the real part of the graphene conductivity.

Practical meaning. Results can be used to create sources and amplifiers of terahertz radiation.

Moiseenko I.M., Popov V.V., Fateev D.V. Negative conductivity of graphene with direct electric current. Nonlinear World. 2021. 

V. 19. № 2. 2021. P. 27−30. DOI: https://doi.org/10.18127/j20700970-202102-06 (In Russian)

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