(Press-News.org)
How can we make wearable devices like Spiderman’s suit that are thin and soft yet also feature various electrical and optical functionalities? The answer lies in producing novel materials that go far beyond the performance of existing materials and developing technology that enables the precise control of the physical properties of such materials.
Separating transition metal dichalcogenide (TMD) into a single layer just like graphene makes it transform into a thin, two-dimensional (2D) film material that exhibits the characteristics of highly performing semiconductors. By stacking two disparate TMD layers, different combinations of TMD types and stacking methods can produce unique properties. For this reason, 2D semiconductors based on heterostructures are attracting attention as an important next-generation material for the electronics industry throughout academia and industries around the world. However, it is still quite challenging to commercialize them due to the difficulty of controlling with precision the physical properties of their quasiparticles.
Professor Kyoung-Duck Park, Yeonjeong Koo, and Hyeongwoo Lee from the Department of Physics at POSTECH conducted a joint research with the team from ITMO University in Russia led by Professor Vasily Kravtsov to develop a multifunctional tip-enhanced spectroscopy that dynamically controls the quasiparticles of a 2D material in a small space. The team successfully controlled semiconductor particles such as interlayer excitons and interlayer trions that are formed at TMD heterobilayers by using the spectroscopy at about the 20nm level.
Like excitons, interlayer excitons of TMD heterobilayers exhibit photoluminescence (PL), which is one of the properties of semiconductor materials. Interlayer excitons, which are electrically neutral quasiparticles, can be used in next-generation semiconductor devices with less heat as they are part light and part matter. They can also be used as a light source for quantum information technologies due to their longer coherence time than those of excitons. Still, there are several hurdles to overcome in their application. They have very low luminous efficiency at room temperature, and it is difficult to modulate their luminous energy.
The POSTECH team led by Professor Park, which had proposed technology for controlling excitons in nano-scale spaces in its previous research, successfully developed the multifunctional tip-enhanced spectroscopy that can be adjusted by gigapascal (GPa)-scale pressure and near-field intensity.
The spectroscopy can increase interlayer excitons’ luminous efficiency by about 9,000 times and dynamically modulate their luminous energy (the color of the light). In addition, the tip-based hot electron injection technology enabled the team to achieve the world’s first dynamic control of quasiparticle conversion between interlayer excitons and interlayer trions.
The most significant advantage of the research breakthrough is that it helps dynamically control the physical properties of the quasiparticles under the condition of room temperature and atmospheric pressure and analyze in real time the optical characteristics of semiconductor particles with the spatial resolution of about 20nm, which is far shorter than the wavelength of light.
Yeonjeong Koo, one of the two co-first authors of the research paper, explained, “The spectroscopy the team developed can be employed in identifying new physical properties of individual semiconductor particles such as interlayer excitons from the TMD heterobilayers. I am very much looking forward to the next physical discoveries.”
The research findings are expected to open up possibilities for various applications of 2D semiconductors based on heterostructures that are being extensively studied as a next-generation material. The fact that basic research in measuring instrument development contributed greatly to the outcome garnered even more attention in the field.
The technology is also expected to be used in developing high luminance, ultrathin wearable optoelectronic devices. The achievement is all the more meaningful in the current situation where the U.S., Japan, and China are vying for dominance in the semiconductor equipment market and putting up technology barriers.
The research, recently published in Light: Science & Applications, an international journal in optics, was supported by the Ministry of Science and ICT, National Research Foundation of Korea, and Samsung Science and Technology Foundation.
END
Contrary to earlier research findings, people of power - think about politicians, celebrities or bullies in school - turn out to be no less concerned about their reputation, compared to those who have less influence and control within the society.
Previously, it has been assumed that since those who have the upper hand in the society - unlike the ‘powerless’ - are able to get away with commonly unacceptable behaviour (e.g. aggression and exploitation), would care less about any potential damages to their reputation.
However, a recent study by scientists at the University of Kent (United Kingdom) ...
• Research at Aston University focuses on both creating lab-based meat and its psychological acceptance
• Dr Eirini Theodosiou and Dr Jason Thomas will be speaking at April’s Society matters LIVE event
• Lab made meat on the menu? will take place at Cafe Artum in Hockley Social Club on Thursday 27 April.
Lab made meat will be the topic of the latest Society matters LIVE event from Aston University at Café Artum at Birmingham’s Hockley ...
In a new study, North Carolina State University researchers had 28 high school students create their own machine-learning artificial intelligence (AI) models for analyzing data. The goals of the project were to help students explore the challenges, limitations and promise of AI, and to ensure a future workforce is prepared to make use of AI tools.
The study was conducted in conjunction with a high school journalism class in the Northeast. Since then, researchers have expanded the program to high school classrooms in multiple states, including North Carolina. ...
EBViously, a spin-off from Helmholtz Munich (HMGU), is led by world-leading experts in Epstein-Barr virus biology, genetics, and immunity and was founded to develop a safe and highly effective preventive vaccine against a range of diseases caused by Epstein-Barr virus (EBV), including infectious mononucleosis, immune disorders, multiple sclerosis, and various cancers. The spin-off is based on a project of HMGU supported by the German Center for Infection Research (DZIF). The project leading to the spin-off was co-funded by the DZIF to enable GMP manufacturing ...
Planners have come up with many innovative ways to prevent flooding caused by heavy downpours — from planting rain gardens to installing green roofs.
But in many cases, nothing works quite as well as a simple hole in the ground — a detention basin.
That’s the finding of an analysis by University of Cincinnati geography students in a research collaboration with the Hamilton County Conservation District.
Lead author and UC College of Arts and Sciences doctoral student Man Qi said cities are developing new ways to trap rainwater and direct it where it’s most wanted, especially during droughts. They call these low-impact development practices, which ...
Prostate cancer tumors harboring BRCA1/2 mutations are exceptionally sensitive to PARP inhibitors, while genomic alterations in other DNA damage response (DDR) genes are less responsive. To identify previously unknown genes whose loss has a profound impact on PARP inhibitor response, researchers from Dana-Farber Brigham Cancer Center led a multinational effort to perform genome-wide CRISPR-Cas9 knockout screens. The study goal was to inform the use of PARP inhibitors beyond BRCA1/2-deficient tumors and support reevaluation ...
Professor Patricia Thornley welcomes latest UK energy security plans
But calls for more exploration of bioenergy with carbon capture and storage
She believes plans shouldn’t concentrate solely on energy such as wind and solar power.
A leading biomass scientist at Aston University has welcomed the government’s announcement to ensure UK energy is more secure.
However, Professor Patricia Thornley, director of Aston University’s Energy and Bioproducts Research Institute (EBRI), believes the government ...
An international group of researchers has created a mixed magnon state in an organic hybrid perovskite material by utilizing the Dzyaloshinskii–Moriya-Interaction (DMI). The resulting material has potential for processing and storing quantum computing information. The work also expands the number of potential materials that can be used to create hybrid magnonic systems.
In magnetic materials, quasi-particles called magnons direct the electron spin within the material. There are two types of magnons – optical and acoustic – which refer to the direction of their spin.
“Both optical and acoustic magnons propagate ...
PLYMOUTH MEETING, PA [April 4, 2023] — New research in the April 2023 issue of JNCCN—Journal of the National Comprehensive Cancer Network finds that specially trained oncology infusion room nurses can improve advance care planning (ACP) for patients with advanced cancer. In this study, oncology nurses underwent an immersive, three-day training session on palliative care. As compared to patients who received standard care, those who participated in this targeted and specialized intervention had a ...
Efforts to encourage vaccination might do well to take advantage of the positive feelings and actions between different social groups, according to a study of attitudes toward vaccines among supporters of the Black Lives Matter movement.
The study by UCLA psychologists, published in the journal Social Science and Medicine, found that across all racial, ethnic and income groups, people who expressed support for the BLM movement were less hesitant about receiving COVID-19 vaccines than those who did not. The evidence suggests that altruistic feelings about interactions between ...
