Skip to main content

Transition metal dichalcogenides (TMDs): a new revolution to quantum technologies

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.
Journal Reference:
  1. Carmen Palacios-Berraquero, Dhiren M. Kara, Alejandro R.-P. Montblanch, Matteo Barbone, Pawel Latawiec, Duhee Yoon, Anna K. Ott, Marko Loncar, Andrea C. Ferrari, Mete Atatüre. Large-scale quantum-emitter arrays in atomically thin semiconductors. Nature Communications, 2017; 8: 15093 DOI: 10.1038/NCOMMS15093
Labels:

Comments

Post a Comment

Popular posts from this blog

Nanoimprinting accelerating the fabrication of nano-optical devices

Combining speed with incredible precision, a team of researchers has developed a way to print a nanoscale imaging probe onto the tip of a glass fiber as thin as a human hair, accelerating the production of the promising new device from several per month to several per day. The high-throughput fabrication technique opens the door for the widespread adoption of this and other nano-optical structures, which squeeze and manipulate light in ways that are unachievable by conventional optics. Nano-optics have the potential to be used for imaging, sensing, and spectroscopy, and could help scientists improve solar cells, design better drugs, and make faster semiconductors. A big obstacle to the technology's commercial use, however, is its time-consuming production process. The new fabrication method, called fiber nanoimprinting, could unplug this bottleneck. It was developed by scientists at the Molecular Foundry, located at the Department of Energy's Lawrence Berkeley Nat...
Post a Comment
Read more

Intel's upcoming 10-nanometer chip manufacturing technology

At long last, chip giant  Intel  (NASDAQ: INTC) opened up about its upcoming 10-nanometer chip manufacturing technology, at its first-ever Technology and Manufacturing Day. The company has -- frustratingly -- kept key details of this technology under wraps for years now, but Intel is now putting them out there for all to see.  Without further ado, let's look at what Intel had to tell us about this new tech. A large jump in density Let's talk performance Competitive comparison and no yield information Image source: Intel. Chipmakers generally like to reduce the area of its transistors with major new technology shifts. This area reduction is important in reducing transistor costs on a yield-normalized basis, a really important factor for product cost. Chipmakers are ultimately able to cram more features and functionality into a chip while maintaining reasonable cost structures. Intel says that in moving from 14 nanometers to 10, it's delivering an incre...
Post a Comment
Read more

Hybrid graphene and CNT anode battery

Rice University scientists have created a rechargeable lithium metal battery with three times the capacity of commercial lithium-ion batteries by resolving something that has long stumped researchers: the dendrite problem. The Rice battery stores lithium in a unique anode, a seamless hybrid of graphene and carbon nanotubes. The material first created at Rice in 2012 is essentially a three-dimensional carbon surface that provides abundant area for lithium to inhabit. The anode itself approaches the theoretical maximum for storage of lithium metal while resisting the formation of damaging dendrites or "mossy" deposits. Dendrites have bedeviled attempts to replace lithium-ion with advanced lithium metal batteries that last longer and charge faster. Dendrites are lithium deposits that grow into the battery's electrolyte. If they bridge the anode and cathode and create a short circuit, the battery may fail, catch fire or even explode. Rice researchers led by chemist...
Post a Comment
Read more