London: Researchers have now set a new world record by creating the world's smallest and most sensitive microwave detector.
This new record has been made beating the previous record by fourteen-fold, an advance which may help in making ultra-sensitive cameras and accessories for emerging quantum computers.
According to the researchers at Finland's Aalto University, the detector which is smaller than a human blood cell has a very simple design having tiny pieces of superconducting aluminum and a single golden nanowire.
With this design , there is effecient absorption of incoming photons and very sensitive readout.
"For us size matters. The smaller the better. With smaller detectors, we get more signal and cheaper price in mass production," said Mikko Mottonen, the leader of the record-breaking Quantum Computing and Devices research group.
The European Research Council (ERC) has recently awarded Mottonen a prestigious proof of concept grant to develop the detector towards commercial applications.
The new detector works at a hundredth of a degree above absolute zero temperature. Thermal disturbances at such low temperatures are so weak that the research team could detect energy packets of only a single zeptojoule. That is the energy needed to lift a red blood cell by just a single nanometre.
The second key development concerns the amplification of the signal arising from the tiny the energy packets.
To this end, the scientists used something called positive feedback, which means that there is an external energy source that amplifies the temperature change arising from the absorbed photons.
Microwaves are currently used in mobile phone communications and satellite televisions, thanks to their ability to pass through the walls.
More sensitive microwave detectors may lead to great improvements of the present communication systems and measurement techniques.
"Existing superconducting technology can produce single microwave photons. However, detection of such travelling photons efficiently is a major outstanding challenge. Our results provide a leap towards solving this problem using thermal detection," said Joonas Govenius, the first author of the work.
The findings were published in the journal Physical Review Letters.
(With Agency input)
