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Revolutionizing Photonics: Researchers Achieve Unprecedented Upconversion Efficiency

Scientists at the National University of Singapore (NUS) have introduced a groundbreaking concept known as “supercritical coupling,” which significantly boosts the efficiency of photon upconversion. This innovation not only overturns existing paradigms but also opens a new direction in the control of light emission.

Photon upconversion, the process of converting low-energy photons into higher-energy ones, is a crucial technique with broad applications, ranging from super-resolution imaging to advanced photonic devices. Despite considerable progress, the quest for efficient photon upconversion has faced challenges due to inherent limitations in the irradiance of lanthanide-doped nanoparticles and the critical coupling conditions of optical resonances.

The concept of “supercritical coupling” plays a pivotal role in addressing these challenges. This fundamentally new approach, proposed by a research team led by Professor LIU Xiaogang from the NUS Department of Chemistry and his collaborator, Dr Gianluigi ZITO from the National Research Council of Italy, leverages on the physics of “bound states in the continuum” (BICs). BICs are phenomena that enable light to be trapped in open structures with theoretically infinite lifetimes, surpassing the limits of critical coupling. These phenomena are different from the usual behavior of light.

Israeli Scientists Find New Way to Treat Cancer

Israeli scientists have made yet another cancer treatment breakthrough, this time using nanosized polymers. Researchers from Ben Gurion University say they developed a way to selectively deliver chemotherapeutic drugs to blood vessels that feed tumors and metastases.

The polymer eliminates colorectal cancer liver metastases and prolongs mice survival, after a single dose-therapy, they said. The findings were published in Nano Today, a leading journal in the field of nanotechnology.

A nanosized polymer is a polymer that has been engineered to have dimensions in the nanometer range. By comparison, a human hair is about 80,000–100,000 nanometers wide. These tiny particles offer unique properties that make them desirable for a wide range of applications.

Good as gold — improving infectious disease testing with gold nanoparticles

Abstract: By harnessing the power of composite polymer particles adorned with gold nanoparticles, a group of researchers have delivered a more accurate means of testing for infectious diseases.

Details of their research was published in the journal Langmuir.

The COVID-19 pandemic reinforced the need for fast and reliable infectious disease testing in large numbers. Most testing done today involves antigen-antibody reactions. Fluorescence, absorptions, or color particle probes are attached to antibodies. When the antibodies stick to the virus, these probes visualize the virus’s presence. In particular, the use of color nanoparticles is renowned for its excellent visuality, along with its simplicity to implement, with little scientific equipment needed to perform lateral flow tests.

Redefining Quantum Communication: Researchers Have Solved a Foundational Problem in Transmitting Quantum Information

Quantum electronics represents a significant departure from conventional electronics. In traditional systems, memory is stored in binary digits. In contrast, quantum electronics utilizes qubits for storage, which can assume various forms, including electrons trapped in nanostructures known as quantum dots. Nonetheless, the ability to transmit information beyond the adjacent quantum dot poses a substantial challenge, thereby limiting the design possibilities for qubits.

Now, in a study recently published in Physical Review Letters, researchers from the Institute of Industrial Science at the University of Tokyo are solving this problem: they developed a new technology for transmitting quantum information over perhaps tens to a hundred micrometers. This advance could improve the functionality of upcoming quantum electronics.

Reimagining quantum dot single-photon sources: A breakthrough in monolithic Fabry-Perot microcavities

Self-assembled semiconductor quantum dots (QDs) represent a three-dimensional confined nanostructure with discrete energy levels, which are similar to atoms. They are capable of producing highly efficient and indistinguishable single photons on demand and are important for exploring fundamental quantum physics and various applications in quantum information technologies. Leveraging traditional semiconductor processes, this material system also offers a natural integration-compatible and scalable platform.

Scientists make ‘major finding’ with nanodevices that can seemingly produce energy out of thin air: ‘Contradicting prior understanding’

Two scientists at the Swiss Laboratory of Nanoscience for Energy Technologies in the School of Engineering may have hit upon a way to simultaneously produce clean water and clean electricity, all with zero pollution.

Giulia Tagliabue, the head of the laboratory, and Tarique Anwar, a PhD student, focused their research on hydrovoltaic effects, which can harness the power of evaporation to provide a continuous flow of energy in order to harvest electricity using specialized nanodevices.

In less technical terms: It’s a way to create clean energy using the power of evaporation. And scientists are taking interest in it due to its planet-friendliness.

Pushing material boundaries for better electronics

A recently tenured faculty member in MIT’s departments of Mechanical Engineering and Materials Science and Engineering, Kim has made numerous discoveries about the nanostructure of materials and is funneling them directly into the advancement of next-generation electronics.

His research aims to push electronics past the inherent limits of silicon — a material that has reliably powered transistors and most other electronic elements but is reaching a performance limit as more computing power is packed into ever smaller devices.

Today, Kim and his students at MIT are exploring materials, devices, and systems that could take over where silicon leaves off. Kim is applying his insights to design next-generation devices, including low-power, high-performance transistors and memory devices, artificial intelligence chips, ultra-high-definition micro-LED displays, and flexible electronic “skin.” Ultimately, he envisions such beyond-silicon devices could be built into supercomputers small enough to fit in your pocket.

Levitated Nanoresonator Breaks Quality-Factor Record

A nanoresonator trapped in ultrahigh vacuum features an exceptionally high quality factor, showing promise for applications in force sensors and macroscopic tests of quantum mechanics.

Nanomechanical oscillators could be used to build ultrasensitive sensors and to test macroscopic quantum phenomena. Key to these applications is a high quality factor (Q), a measure of how many oscillation cycles can be completed before the oscillator energy is dissipated. So far, clamped-membrane nanoresonators achieved a Q of about 1010, which was limited by interactions with the environment. Now a team led by Tracy Northup at the University of Innsbruck, Austria, reports a levitated oscillator—a floating particle oscillating in a trap—competitive with the best clamped ones [1]. The scheme offers potential for order-of-magnitude improvements, the researchers say.

Theorists have long predicted that levitated oscillators, by eliminating clamping-related losses, could reach a Q as large as 1012. Until now, however, the best levitated schemes, based on optically trapped nanoparticles, achieved a Q of only 108. To further boost Q, the Innsbruck researchers devised a scheme that mitigated two important dissipation mechanisms. First, they replaced the optical trap with a Paul trap, one that confines a charged particle using time-varying electric fields instead of lasers. This approach eliminates the dissipation associated with light scattering from the trapped particle. Second, they trapped the particle in ultrahigh vacuum, where the nanoparticle collides with only about one gas molecule in each oscillation cycle.

New Alzheimer’s treatment slows disease with nanoparticles

Alzheimer’s is the most common form of dementia, affecting an estimated 6.7 million people in the US. Researchers seeking an effective treatment for the affliction have, over the last 30 years, focused their efforts on a protein known as amyloid beta (A-beta), which form clumps in the brain.

These clumps of A-beta proteins attack nerve cells, resulting initially in short-term memory impairment and later in the loss of judgment, language and thought processes.

Other researchers have previously developed an antibody which can identify and attach itself to A-beta proteins and delay the progression of Alzheimer’s in patients with early-to-mild cognitive impairment by up to 36%.