POWERlab News

Elison Matioli at TEDx Arendal © TEDx Arendal/Mona Hauglid

Elison Matioli at TEDx Arendal: Can materials mimic the human body?

— Elison Matioli, head of the POWERlab in the School of Engineering, delivered a TEDx talk on his research at TEDx Arendal in November, 2022. The video of his talk on new and efficient semiconductor device concepts has recently been published on the TEDx website.

© iStock/wragg

Electronic metadevices break barriers to ultra-fast communications

— EPFL researchers have come up with a new approach to electronics that involves engineering metastructures at the sub-wavelength scale. It could launch the next generation of ultra-fast devices for exchanging massive amounts of data, with applications in 6G communications and beyond.

Vanadium Dioxide (VO2), a compound capable of “remembering” the entire history of previous external stimuli. © POWERlab / 2022 EPFL

Researchers discover a material that can learn like the brain

— EPFL researchers have discovered that Vanadium Dioxide (VO2), a compound used in electronics, is capable of “remembering” the entire history of previous external stimuli. This is the first material to be identified as possessing this property, although there could be others.

© 2021 POWERlab EPFL

Charitat Award for Luca Nela at the ISPSD'21

— The paper entitled “High-Performance Enhancement-Mode AlGaN/GaN Multi-Channel Power Transistors” presented by Luca Nela from the POWERlab has received the Charitat Award at the 33rd International Symposium on Power Semiconductor Devices and ICs (ISPSD 2021), held in Nagoya, Japan. This is the second Charitat Award in a row after the previous one at ISPSD 2020 in Vienna with the paper “High-Frequency GaN-on-Si power integrated circuits based on Tri-Anode SBDs” also by Luca Nela, Elison Matioli, and co-authors from the POWERlab.

The transistor developed by EPFL researchers can transistor can substantially reduce the resistance and cut the amount of heat dissipation in high-power systems © 2021 EPFL

New nanotransistors keep their cool at high voltages

— Power converters play an essential role in electric vehicles and solar panels, for example, but tend to lose a lot of power in the form of heat in the electricity conversion process. Thanks to a new type of transistor developed at EPFL, these converters can perform at substantially improved efficiencies, especially in high-power applications.

© 2020 EPFL

Transistor-integrated cooling for a more powerful chip

— EPFL researchers have created a single chip that combines a transistor and micro-fluidic cooling system. Their research, which has been published in Nature, should help save energy and further shrink the size of electronic components.

All news

March 2020 – Interview for Nature podcast
Ultra-fast electrical switches, and computing heart health

May. 2016 – Interview for Canal do Otario 
Interview for a brazillian channel
(in portuguese) [link]

 

Oct. 2016 – European Union – Brussels 

Research cooperation agreement signed between EU and Brazil

Feb. 2016 – Interview for Jornal da Cultura 

Interview for TV cultura – Brazil

(in portuguese) [link]

Feb. 2016 – Featured on Globo-G1

Brasileiro recebe 1.75 milhão de euros para desenvolver pesquisa na Europa

Feb. 2015 – Interview for Canal do Otario 

Interview for a brazillian channel

(in portuguese) [link]

 

Jan. 2015 – Featured on Globo-G1

Brasileiro ex-aluno de escola pública é professor em universidade na Suíça

Nov. 2014 – Seminar Escola Politecnica-USP

Seminar at Escola Politecnica

Universidade de Sao Paulo – Brazil

(in portuguese) [link]

Oct. 2014 – Featured on TV cultura/Univesptv

Interview for a brazillian TV channel

(in portuguese) [link]

Oct. 2014 – Featured on Globo-G1

Interview for Globo-G1 website – Brazil

(in portuguese) [link]

 

Previous news
(prior to EPFL)

Dec 2013 – 2012 IEEE Electron Devices Society George E. Smith Award

Our paper received the 2012 IEEE George Smith Award as the best paper published in IEEE Electron Device Letters in 2012

[MIT news] [IEEE]

Aug 2012 – Nature Light: Science & Applications: Photonics: preferred orientations [link]

Researchers have designed a light-emitting diode (LED) that produces bright directional polarized blue light. The device, developed at the University of California at Santa Barbara in the USA by Elison Matioli and collaborators, is based on a variant of the semiconductor gallium nitride, grown on a specifically crystal direction that yields emission of polarized light. The researchers improved light extraction from the device by drilling aligned arrays of holes at precisely defined intervals into the substrate. This photonic crystal structure selectively enhances the emission of polarized light for particular emission angles by up to a factor of 1.8. High-brightness LEDs emitting polarized light are of interest for flat-screen displays, and also for household lighting because they minimize the glare from light reflections.

 

Feb 2012 – Semiconductor Today Magazine: Tri-gate applied to make normally-off nitride semiconductor transistors [link]

Massachusetts Institute of Technology (MIT) has applied tri-gate technology to create new normally-off nitride semiconductor transistors, increasing on/off current ratios to eight orders of magnitude and reducing the sub-threshold slope to 86mV/dec on average [Bin Lu et al, IEEE Electron Device Letters, published online 27 January 2012].

 

May 2011 – Compound Semiconductors Magazine: Nitride Cells Start Delivering High Efficiencies [link]

Reduced internal electric fields, rougher surfaces and the introduction of superlattices are helping to drive up the efficiencies of nitride solar cells compared to lasers, transistors and LEDs, solar cells based on nitrides tend to deliver poor performances. But these materials can yield efficient photovoltaics, according to research by both a pair of Japanese Universities and by a team led by the University of California, Santa Barbara (UCSB).

 

Mar 2011 – Semiconductor Today Magazine: Seeking to unlock wide-range potential of nitride photovoltaics [link]

Up to now, nitride semiconductor solar cells have only responded to the high-energy, short-wavelength end of the solar spectrum. Mike Cooke reports on recent attempts to extend this range.

 

Feb 2011 – LaserFocusWorld Magazine – Newsbreaks: Short-wavelength solar cells have high external quantum efficiency [link]

Indium gallium nitride (InGaN)-based semiconductors have large bandgaps, which has allowed the creation of ultraviolet and bright blue-emitting LEDs and lasers. However, a large bandgap can be a plus for use in detectors and solar cells as well, because they have a high response to short-wavelength light (down to 370 nm). Researchers at the University of California–Santa Barbara and the École Polytechnique (Palaiseau, France) have demonstrated InGaN/GaN solar cells that have an internal quantum efficiency as high as 97% and a peak external quantum efficiency (EQE) of 72%—the latter achieved by inducing a 41 nm (root mean square) surface roughness during fabrication…

 

Jan 2011 – Semiconductor Today Magazine: Nitride solar cell achieves peak EQE of 72% [link]

University of California Santa Barbara (UCSB) researchers have produced nitride semiconductor photovoltaic devices with external quantum efficiencies (EQE) of up to 72% [Elison Matioli et al, Appl. Phys. Lett., vol98, p021102, 2011]. One of the researchers, Claude Weisbuch, is also associated with Ecole Polytechnique in France…

 

Sep. 2010 – IOP Science: Could embedded photonic crystals be the way? Light-emitting diodes (LEDs) for high-efficiency solid-state lighting: [link]

High-efficiency LEDs are considered the best choice for future lighting due to their remarkable efficiency in transforming electricity into light. High-efficiency LEDs have only recently been demonstrated thanks to improvements in semiconducting GaN quality leading to better internal quantum efficiency, and to the implementation of high-efficiency light extraction concepts. The latter are made necessary by the fact that light is normally trapped inside the semiconductor by total internal reflection when it attempts to escape the LED. Recent advances in photonic crystals (PhCs) show that they could become the best technique to yield high-efficiency LEDs…

 

Aug 2010 – Nanotechweb Magazine – Lab talk: LEDs for high-efficiency solid-state lighting [link]

High-efficiency LEDs are considered the best choice for future lighting due to their remarkable efficiency in transforming electricity into light. High-efficiency LEDs have only recently been demonstrated thanks to improvements in semiconducting GaN quality leading to better internal quantum efficiency, and to the implementation of high-efficiency light extraction concepts. The latter are made necessary by the fact that light is normally trapped inside the semiconductor by total internal reflection when it attempts to escape the LED. Recent advances in photonic crystals (PhCs) show that they could become the best technique to yield high-efficiency LEDs…

 

Mar. 2010 – Photonics.com Magazine: Green Photonics [link]

Recent demonstration of an LED with an extraction efficiency of about 94 percent designed and fabricated by Dr. Elison Matioli and researchers from the University of California at Santa Barbara, Harvard University and Ecole Polytechnique in France. They showed that embedded two-dimensional photonic crystal LEDs present an enhanced directional light emission compared to nonphotonic crystal LEDs.

 

Feb. 2010 – Semiconductor International Magazine: LED’s at Photonics West – 94% of the Light Gets Out!

Academics and industrialists from all over the world provided a series of first class papers on LED’s at this years Photonics West in San Francisco. For me, the most impressive was a paper by Elison Matioli from UC Santa Barbara (UCSB) who reported a 94% extraction efficiency by burying a photonic crystal in a working LED.