Development of the device brings researchers a big step closer to higher speed electronics and higher performance electrical and optical integrated circuits.
The mixing device accepts two electrical inputs and produces an optical signal that was measured at frequencies of up to 22.7 gigahertz. The frequency range was limited by the bandwidth of the detector employed in the measurements, not by the transistor device.“
"In addition to the usual current-modulation capability, the tunnel junction provides an enhanced means for voltage-controlled modulation of the photon output of the transistor laser,” said Nick Holonyak Jr., a John Bardeen Chair Professor of Electrical and Computer Engineering and Physics at the U. of I. “This offers new capabilities and a much greater sensitivity for unique signal-mixing and signal-processing applications.”
To make the device, the researchers first placed a quantum well inside the base region of a transistor laser. Then they created a tunnel junction within the collector region. They describe the fabrication and operation of the mixing device in the March 13 issue of the journal Applied Physics Letters.
“Within the transistor laser, the tunneling process occurs predominantly through a process called photon-assisted absorption,” said Milton Feng, the Holonyak Chair Professor of Electrical and Computer Engineering.
The tunneling process begins in the quantum well, where electrons and holes combine and generate photons, Feng said. Those photons are then reabsorbed to create new pairs of electrons and holes used for voltage modulation.
“The tunnel junction makes it possible to annihilate an electron in the quantum well, and then tunnel an electron out to the collector by the tunnel contact,” Feng said.
The transistor output is sensitive to third-terminal voltage control because of the electrons tunneling from the base to the collector, which also creates an efficient supply of holes to the quantum well for recombination.
“This is a new type of transistor,” said Holonyak, who also is a professor in the university’s Center for Advanced Study, one of the highest forms of campus recognition. “We are using the photon internally to modify the electrical operation and make the transistor itself a different device with additional properties.”
High-speed signal mixing, for example, is made possible by the nonlinear coupling of the internal optical field to the base electron-hole recombination, minority carrier emitter-to-collector transport, and the base-to-collector electron tunneling at the collector junction, the researchers report.
The sensitivity of the tunnel-junction transistor laser to voltage control enables the device to be directly modulated by both current and voltage. This flexibility facilitates the design of new nonlinear signal processing devices for improved optical power output.
“The metamorphosis of the transistor is not yet complete,” Holonyak said. “We’re still working on it, and the transistor is still changing.”
Co-authors of the paper are graduate research assistant and lead author Han Wui Then, graduate student Hsin-Yu Wu and senior research scientist Gabriel Walter.
James E. Kloeppel | University of Illinois
Further reports about: > Ferchau Engineering > High-Speed Signal Mixer > Mixer > Physic > Quantum > Transistor > Transistor Laser > higher performance electrical and optical integrated circuits > laser system > microwave signal mixer > optical signal > photon-assisted absorption > signal-processing applications > transistor device > tunnel junction > tunnel-junction transistor laser > voltage modulation
NASA laser communications to provide Orion faster connections
30.03.2017 | NASA/Goddard Space Flight Center
Pinball at the atomic level
30.03.2017 | Max-Planck-Institut für Struktur und Dynamik der Materie
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
30.03.2017 | Health and Medicine
30.03.2017 | Health and Medicine
30.03.2017 | Medical Engineering