Wi-Fi and cellular data traffic are increasing exponentially but, unless the capacity of wireless links can be increased, all that traffic is bound to lead to unacceptable bottlenecks.
Upcoming 5G networks are a temporary fix but not a long-term solution. For that, researchers have focused on terahertz frequencies, the submillimeter wavelengths of the electromagnetic spectrum. Data traveling at terahertz frequencies could move hundreds of times faster than today’s wireless.
In 2017, researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) discovered that an infrared frequency comb in a quantum cascade laser could offer a new way to generate terahertz frequencies. Now, those researchers have uncovered a new phenomenon of quantum cascade laser frequency combs, which would allow these devices to act as integrated transmitters or receivers that can efficiently encode information.
The research is published in Optica.
“This work represents a complete paradigm shift for the way a laser can be operated,” said Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering and senior author of the paper. “This new phenomenon transforms a laser — a device operating at optical frequencies — into an advanced modulator at microwave frequencies, which has a technological significance for efficient use of bandwidth in communication systems.”
This work represents a complete paradigm shift for the way a laser can be operated.
Frequency combs are widely-used, high-precision tools for measuring and detecting different frequencies — a.k.a. colors — of light. Unlike conventional lasers, which emit a single frequency, these lasers emit multiple frequencies simultaneously, evenly spaced to resemble the teeth of a comb. Today, optical frequency combs are used for everything from measuring the fingerprints of specific molecules to detecting distant exoplanets.
This research, however, wasn’t interested in the optical output of the laser.
“We were interested in what was going on inside the laser, in the laser’s electron skeleton,” said Marco Piccardo, a postdoctoral fellow at SEAS and first author of the paper. “We showed, for the first time, that a laser at optical wavelengths can operate as a microwave device.”
Inside the laser, the different frequencies of light beat together to generate microwave radiation. The researchers discovered that light inside the cavity of the laser causes electrons to oscillate at microwave frequencies — which are within the communications spectrum. These oscillations can be externally modulated to encode information onto a carrier signal.
“This functionality has never been demonstrated in a laser before,” said Piccardo. “We have shown that the laser can act as a so-called quadrature modulator, allowing two different pieces of information to be sent simultaneously through a single frequency channel and successively be retrieved at the other end of a communication link.”
“Currently, terahertz sources have serious limitations due to limited bandwidth,” said Capasso. “This discovery opens up an entirely new aspect of frequency combs and could lead, in the near future, to a terahertz source for wireless communications.”
Learn more: Laser frequency combs may be the future of Wi-Fi
The Latest on: Terahertz wireless communications
via Google News
The Latest on: Terahertz wireless communications
- 6G will achieve terabits-per-second speeds on September 12, 2018 at 9:20 am
5G’s principal benefits over current wireless platforms are touted as latency reduction ... as well as those in the U.S.’s Center for Converged TeraHertz Communications and Sensing (ComSenTer), which ... […]
- The terahertz computer chip is within reach on April 6, 2018 at 2:21 pm
together with and all optic communication devices, to run 100 times faster. This is through the use of terahertz microchips. The terahertz chip could be used to develop a new generation wireless telec... […]
- Terahertz microchips to make computers 100 times faster on March 26, 2018 at 8:08 pm
This discovery could help fill the 'THz gap' and create new and more powerful wireless devices that could ... enable our computers — and all optic communication devices — to run 100 times faster throu... […]
- Terahertz microchips to make computers 100 times faster: Study on March 26, 2018 at 6:38 am
“This discovery could help fill the ‘THz gap’ and create new and more powerful wireless devices that could transmit ... all optic devices closer to the holy grail of communications – the terahertz chi... […]
- The future of wireless communications is terahertz on February 5, 2018 at 4:00 pm
Electrical and optical engineers in Australia have designed a novel platform that could tailor telecommunication and optical transmissions. They experimentally demonstrated their system using a new tr... […]
- Terahertz Technology Market Report 2017, Trends, Analysis, Share, Estimates and Forecasts to 2022. on September 20, 2017 at 9:42 pm
According to Stratistics MRC, the Global Terahertz Technology Market accounted for $84.53 million in 2015 and is expected to reach $491.27 million by 2022 growing at a CAGR of 28.5% from 2015 to 2022. ... […]
- Terahertz Technology Market: Global Industry Analysis, Size, Share, Growth, Trends, and Forecasts 2016–2024 on July 26, 2017 at 2:07 pm
The terahertz technology market has also a major share from the terahertz communication systems. The terahertz band for communication facilitates the capacity limitations of the wireless systems and a... […]
- Terahertz Technology Market: Global Industry Analysis, Size, Share, Growth, Trends, and Forecasts 2016–2024 on July 25, 2017 at 5:00 pm
The terahertz band for communication facilitates the capacity limitations of the wireless systems and also facilitates the spectrum scarcity and it also enables different applications in the novel nan... […]
- Will graphene radios unlock IoT access to terahertz band? on November 6, 2016 at 10:52 am
to develop a wireless network that operates in the terahertz band. Jornet recently noted from the University of Buffalo, “For wireless communication, the terahertz band is like an express lane. But th... […]
via Bing News