Quantum electronics, electromagnetics, electro-optics, lasers, electronic devices, semiconductors and semiconductor devices.
Specific research topics: 

1. Free Electron quantum optics.
2. Interaction of electron quantum wavefunction with light and matter.
3. Electron beam interaction with electromagnetic waves, free electron lasers, Cerenkov-Smith-Purcell radiation.
4. Millimeter Waves and THz radiation.
5. Radiative energy transmission.
6. Cellular communication from a stratospheric platform.