Recently Researchers have succeeded
to develop a nanodevice that can run 10 times faster than present transistors. The
device enables the generation of high-power terahertz waves which are difficult
to produce otherwise. Terahertz (THz) waves fall between microwave and infrared
radiation in the electromagnetic spectrum, oscillating at frequencies of
between 100 billion and 30 trillion cycles per second. Generation of these
waves have immense impact on security and medical imaging, sensing, cancer
therapy and high-speed wireless communications due to the ability to carry vast
quantities of data. These waves can penetrate paper, clothing, wood and walls.
It can detect air pollution.
However, THz waves are not widely
used because they are costly and cumbersome to generate. But researchers led by
Prof. Elison Matioli, built a nanodevice that can generate extremely high-power
THz waves.
The compact, cheaper fully
electric nanodevice generates high-intensity waves by producing a voltage from
10 V (or lower) to 100 V in the range of a picosecond. The device consists of
two metal plates placed very close together, down to 20 nanometres apart. When potential
difference between these two plates is applied, electrons surge towards one of
the plates (plasma). Once the voltage reaches a certain threshold, the
electrons are emitted almost instantly to the second plate. This rapid movement
enabled by such fast switches creates a high-intensity pulse that produces
high-frequency waves. When hooked up to antennas, the system can produce and
radiate high-power THz waves.
The new nanodevice can create
both high-energy and high-frequency pulses, unlike present high frequency
semiconductor devices, which can only sustain with a few volts before breaking
out. The new device has been proposed to surmount these constraint by nanoplasma and state-of-the-art nanoscale
fabrication techniques
