Active antennas for wireless applications using two-terminal quantum devices

Heterojuction interband tunneling diodes (HITDs) exhibit negative differential resistance (NDR) when biased appropriately. This feature could add functionality to conventional circuits. The high speed of electrons in HITD allows these devices to work at very high frequencies. This work aims to investigate potential RF applications of HITDs. The AC characteristics of HITDs are extracted from experimental data. We used a slot antenna as a load for the HITDs. By proper matching of the circuit impedance and the device biasing, the HITD would oscillate in conjunction with the antenna. A prototype of uniplanar structure suitable for 1.5 GHz operation was fabricated to validate our design approach. The preliminary results are very interesting. Successfully developing viable integrated antennas at millimeter-wave frequencies exploits unique features of these devices and provides useful sources at high frequencies.