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Advanced optoelectronics require materials with newly engineered characteristics. Examples include a class of materials named metal-halide perovskites that have tremendous significance to form perovskite solar cells with photovoltaic efficiencies. Recent advances have also applied perovskite nanocrystals in light-emitting devices. The unusually efficient light emission of cesium lead-halide perovskite may be due to a unique excitonic fine structure made of three bright triplet states that minimally interact with a proximal dark singlet state. Excitons are electronic excitations responsible for the emissive properties of nanostructured semiconductors, where the lowest-energy excitonic state is expected to be long lived and hence poorly emitting (or ‘dark’).

In a new report now published in Science Advances, Albert Liu and a team of scientists in physics and chemistry at the University of Michigan, U.S., and Campinas State University, Brazil, used multidimensional coherent spectroscopy at cryogenic (ultra-cold) temperatures to study the fine structure without isolating the cube-shaped single . The work revealed coherences (wave properties relative to space and time) involving the triplet states of a cesium lead-iodide (CsPbI3) nanocrystal ensemble. Based on the measurements of triplet and inter-triplet coherences, the team obtained a unique exciton fine structure level ordering composed of a dark state, energetically positioned within the bright triplet manifold.

But by the start of December, the developers of several vaccines had announced excellent results in large trials, with more showing promise. And on 2 December, a vaccine made by drug giant Pfizer with German biotech firm BioNTech, became the first fully-tested immunization to be approved for emergency use.

That speed of advance “challenges our whole paradigm of what is possible in vaccine development”, says Natalie Dean, a biostatistician at the University of Florida in Gainesville. It’s tempting to hope that other vaccines might now be made on a comparable timescale. These are sorely needed: diseases such as malaria, tuberculosis and pneumonia together kill millions of people a year, and researchers anticipate further lethal pandemics, too.

The COVID-19 experience will almost certainly change the future of vaccine science, says Dan Barouch, director of the Center for Virology and Vaccine Research at Harvard Medical School in Boston, Massachusetts. “It shows how fast vaccine development can proceed when there is a true global emergency and sufficient resources,” he says. New ways of making vaccines, such as by using messenger RNA (mRNA), have been validated by the COVID-19 response, he adds. “It has shown that the development process can be accelerated substantially without compromising on safety.”

Although no list like this can be definitive, we polled dozens of researchers over the past year to develop a diverse line-up of ten software tools that have had a big impact on the world of science. You can weigh in on our choices at the end of the story.


From Fortran to arXiv.org, these advances in programming and platforms sent biology, climate science and physics into warp speed.

Our internal systems showed no evidence of unauthorized access or compromise in any on-premises and production environments.

Our software remains safe to use, Kleczynski added.

After today’s disclosure, Malwarebytes becomes the fourth major security vendor targeted by the UNC2452/Dark Halo threat actor, which US officials have linked to a Russian government cyber-espionage operation.

This is the third installment in a three-part series. Read parts one and two.

In the third and final part of our series, Fusion Industry Association director Andrew Holland tells Asia Times’ correspondent Jonathan Tennenbaum how the private sector is leap-frogging government programs in the race to develop commercial fusion power plants.

Andrew Holland: So now the private sector is coming in. You mentioned high-temperature superconductors. That’s an important new thing. There’s a whole range of new developments that come from outside of the fusion space that are now being applied.