Phase Coherence and Temperature Dependence of Current-Voltage Characteristics at Low-Current and Low-Voltage Region of Double-Barrier Resonant-Tunneling Diode

At sufficiently low temperatures, e.g., below 10 K, current in current–voltage (I–V) characteristics of double-barrier resonant-tunneling diodes (DBRTDs) in the low-current and low-voltage region is inversely proportional to the phase coherence length. However, with increasing temperature, this proportional behavior no longer holds due to thermal energy spread around the Fermi energy in the emitter. In this study, the temperature range in which current amplitude is inversely proportional to the phase coherence length is theoretically derived. The temperature range is dependent on the structural parameters of DBRTDs. By choosing appropriate device parameters, we can make the current amplitude inversely proportional to the phase coherence length even at relatively high temperatures, e.g., 77 K. These results are highly useful for estimating electron phase coherence length over a wide temperature range and for studying the temperature dependence of the phase coherence length using DBRTDs.