Transition metal dichalcogenides (TMDs) are layered semiconductors that can be exfoliated into layers only a few atoms thick. Recent research has shown that some TMDs can contain quantum light sources that can emit single photons of light.
Until now, the occurrence of these quantum light emitters has been random. Now, researchers in the Graphene Flagship working at the University of Cambridge, UK, have created large scale arrays of these quantum emitters in different TMD materials.
The work, also involving researchers from Harvard University, US, is published in Nature Communications. This new approach leads to large quantities of on-demand, single photon emitters, paving the way for integrating ultra-thin, single photons in electronic devices.
Quantum light emitters, or quantum dots, are of interest for many different applications, including quantum communication and networks. Until now, it has been very difficult to produce large arrays of quantum emitters close together while keeping the high quality of the quantum light sources.
"It's almost a Goldilocks problem - it seems like one either obtains good single photon sources, or good arrays but not both at the same time. Now, all of a sudden, we can have hundreds of these emitters in one sample," said Mete Atatüre, a professor at the Cavendish Laboratory of the University of Cambridge.
The random occurrences of quantum dots in TMD made systematic investigation difficult. "The ability to deterministically create our sources has made a dramatic change in the way we do our day-to-day research. Previously it was pure luck, and we had to keep our spirits high even if we didn't succeed. Now, we can do research in a more systematic way," said Atatüre.
Not only does this new method make performing research more straightforward, but it also leads to improvements in the emitters themselves: "The quality of the emitters that we create on purpose seems to be better than the natural quantum dots."
Dhiren Kara, a researcher at the Cavendish Laboratory, said "There is lots of mystery surrounding these emitters, in how they originate and how they work. Now, one can directly create the emitters and not have to worry about waiting for them to appear randomly. In that sense, it speeds up a lot of the science."
To create the quantum light sources, the researchers cut an array of nanoscale pillars into silica or nanodiamond, and then suspended the few-atom-thick TMD layer on top of the pillars. The quantum emitters are then created in the TMD where it is supported by the pillars, so it is possible to choose exactly where the single photons should be generated.
"The fact that the emitters are generated in a mechanical way is good, because it means that they are quite robust, and material independent," said Carmen Palacios-Berraquero, a researcher at the Cavendish Laboratory and first author of the work.
The deterministic and robust generation of quantum sources means new opportunities for hybrid structures of photonic and electronic functions layered together. The quantum arrays are fully scalable and compatible with silicon chip fabrication.
Andrea Ferrari, Science and Technology Officer and Chair of the Management Panel of the Graphene Flagship, was also involved in the research. He added "Quantum technologies are recognized as key investment areas for Europe, with a new Quantum Flagship recently announced. It is great to see that layered materials have now a firm place amongst the promising approaches for generation and manipulation of quantum light and could be enablers of a future integrated technology."
Sophia Lloyd | EurekAlert!
NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center
Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
17.11.2017 | Physics and Astronomy
17.11.2017 | Health and Medicine
17.11.2017 | Studies and Analyses