Methods and apparatus for terahertz wave amplitude modulation

摘要

A wave amplitude modulator for modulating a transmitted electromagnetic wave includes one or multiple self-gated capacitively coupled pair(s) of electron layers such as semiconductor or semimetal layers. Two electrical contacts are placed to each layer of electrons of the self-gated pair(s), and a power source is electrically connected to them. The power source, by varying the voltage applied between layers of electrons, tunes the electron density thereof, thereby adjusting the optical conductivity thereof, and the change in the optical conductivity of the layers of electrons causes an amplitude modulation of the transmitted electromagnetic wave passing through the capacitively coupled layers of electrons.

主权项

1. A wave amplitude modulator for modulating a transmitted electromagnetic wave, the modulator comprising:
a substrate; a first tunable two-dimensional electron-gas layer disposed on the substrate; an insulator material disposed on the tunable two-dimensional electron-gas layer; a graphene layer configured as a second tunable two-dimensional electron-gas material disposed on the insulator material; and a power source electrically coupled to both the first and second two-dimensional electron-gas layers, wherein the power supply provides a voltage between the first and second two-dimensional electron-gas layers, wherein the applied voltage tunes the electron concentration of the two-dimensional electron-gas layers by inducing the formation of holes in one of the two-dimensional electron-gas layers, while inducing the formation of corresponding electrons in the other of the two-dimensional electron-gas layers and thereby adjusting the optical conductivity thereof, and wherein the change in the optical conductivity causes a modulation of the transmitted wave passing through the modulator.