The Quantum Magnetron: Modeling a Chip-Scale, Solid-State THz Source in 2D Materials

We propose a chip-scale, solid-state, THz-emitting quantum analogue of the magnetron — a device that generates microwave radiation using the cyclotron motion of electrons in a magnetic field. At a fixed magnetic field strength, magnetron frequency and size is limited in part by the cyclotron orbit and therefore mass of the electrons. However, electrons in some 2D materials exhibit dramatically reduced effective mass while retaining the ballistic dynamics required for cyclotron motion. We therefore introduce a new model of a magnetron supporting THz emission frequency and chip-scale device size. This reduced scale demands a quantum treatment of the electrons' dynamics which are explored in this work. We show a correspondence between this device and its classical progenitor, including energy transfer into a coupled resonant mode. This architecture addresses a longstanding THz gap with a compact solid-state device leveraging recent advances in 2D materials.