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A nitrogen-vacancy (NV) center is a defect in the crystal structure of diamond, where a nitrogen atom replaces a carbon atom in the diamond lattice and a neighboring site in the lattice is vacant. This and other fluorescent defects in diamond, known as color centers, have attracted researchers’ attention owing to their quantum properties, such as single-photon emission at room temperature and with long coherence time. Their many applications include quantum information encoding and processing, and cell marking in biological studies.

Microfabrication in diamond is technically difficult, and nanodiamonds with color centers have been embedded in custom-designed structures as a way of integrating these quantum emitters into photonic devices. A study conducted at the University of São Paulo’s São Carlos Institute of Physics (IFSC-USP) in Brazil has established a method for this, as described in an article published in the journal Nanomaterials.

“We demonstrated a method of embedding fluorescent nanodiamonds in designed for this purpose, using two-photon polymerization [2PP],” Cleber Mendonça, a professor at IFSC-USP and last author of the article, told Agência FAPESP. “We studied the ideal concentration of nanodiamond in the photoresist to achieve structures with at least one fluorescent NV center and good structural and optical quality.” The photoresist is a light-sensitive material used in the fabrication process to transfer nanoscale patterns to the substrate.

Engelbart grew up on a small farm in Southeast Portland where his father operated a radio store.

He graduated from Franklin High School in 1942 and enrolled at Oregon State College, now called Oregon State University, to study electrical engineering.

When World War II interrupted his studies, he spent two years working as a Navy radio and radar technician in the Philippines.

EPFL researchers have developed a hybrid device that significantly improves existing, ubiquitous laser technology.

The team at EPFL’s Photonic Systems Laboratory (PHOSL) has developed a chip-scale laser source that enhances the performance of semiconductor lasers while enabling the generation of shorter wavelengths. This pioneering work, led by Professor Camille Brès and postdoctoral researcher Marco Clementi from EPFL’s School of Engineering represents a significant advance in the field of photonics, with implications for telecommunications, metrology, and other high-precision applications.

Innovative integration for improved coherence and visibility.

A groundbreaking study introduces advanced nanometric optomechanical cavities, paving the way for more efficient quantum networks and improving quantum computing and communication technologies.

The ability to transmit information coherently in the band of the electromagnetic spectrum from microwave to infrared is vitally important to the development of the advanced quantum networks used in computing and communications.

A study conducted by researchers at the State University of Campinas (UNICAMP) in Brazil, in collaboration with colleagues at ETH Zurich in Switzerland and TU Delft in the Netherlands, focused on the use of nanometric optomechanical cavities for this purpose. These nanoscale resonators promote interaction between high-frequency mechanical vibrations and infrared light at wavelengths used by the telecommunications industry.

Bulky and hard to wrangle, molecules have long defied physicists’ attempts to lure them into a state of controlled quantum entanglement, whereby the molecules are intimately linked even at a distance.

Now, for the first time, two separate teams have succeeded in entangling pairs of ultra-cold molecules using the same method: microscopically precise optical ‘tweezer traps’

Quantum entanglement is a bizarre yet fundamental phenomenon of the quantum realm that physicists are trying to tap into to create the first, commercial quantum computers.

Is it possible to invent a computer that computes anything in a flash? Or could some problems stump even the most powerful of computers? How complex is too complex for computation? The question of how hard a problem is to solve lies at the heart of an important field of computer science called computational complexity. Computational complexity theorists want to know which problems are practically solvable using clever algorithms and which problems are truly difficult, maybe even virtually impossible, for computers to crack. This hardness is central to what’s called the P versus NP problem, one of the most difficult and important questions in all of math and science.

This video covers a wide range of topics including: the history of computer science, how transistor-based electronic computers solve problems using Boolean logical operations and algorithms, what is a Turing Machine, the different classes of problems, circuit complexity, and the emerging field of meta-complexity, where researchers study the self-referential nature of complexity questions.

Featuring computer scientist Scott Aaronson (full disclosure, he is also member of the Quanta Magazine Board). Check out his blog: https://scottaaronson.blog/

Read the companion article about meta-complexity at Quanta Magazine: https://www.quantamagazine.org/complexity-theorys-50-year-jo…-20230817/

😀 Amazing breakthrough face_with_colon_three


A group of Spanish researchers have developed a brain-computer interface based on electroencephalograms that allowed a group of 22 users to play a simple multiplayer game. The interface was 94% accurate in translating players’ thoughts into game moves, with each move taking just over 5 seconds. The study was published in Frontiers in Human Neuroscience.

A brain-computer interface is a technology that enables direct communication between the human brain and external devices, such as computers or prosthetic limbs. Brain-computer interfaces work by detecting and interpreting neural signals, typically through electrodes placed on the user’s head. These signals are then translated into actionable commands, allowing individuals to control computers, devices, or applications using their thoughts.

Brain-computer interfaces offer significant potential in medicine, from helping paralyzed individuals regain environmental control to treating neurological disorders. However, their broader adoption is hindered by challenges in accuracy and the extended time required to interpret brain signals.

Introduction and objective: Video games are crucial to the entertainment industry, nonetheless they can be challenging to access for those with severe motor disabilities. Brain-computer interfaces (BCI) systems have the potential to help these individuals by allowing them to control video games using their brain signals. Furthermore, multiplayer BCI-based video games may provide valuable insights into how competitiveness or motivation affects the control of these interfaces. Despite the recent advancement in the development of code-modulated visual evoked potentials (c-VEPs) as control signals for high-performance BCIs, to the best of our knowledge, no studies have been conducted to develop a BCI-driven video game utilizing c-VEPs. However, c-VEPs could enhance user experience as an alternative method. Thus, the main goal of this work was to design, develop, and evaluate a version of the well-known ‘Connect 4’ video game using a c-VEP-based BCI, allowing 2 users to compete by aligning 4 same-colored coins vertically, horizontally or diagonally.

Methods: The proposed application consists of a multiplayer video game controlled by a real-time BCI system processing 2 electroencephalograms (EEGs) sequentially. To detect user intention, columns in which the coin can be placed was encoded with shifted versions of a pseudorandom binary code, following a traditional circular shifting c-VEP paradigm. To analyze the usability of our application, the experimental protocol comprised an evaluation session by 22 healthy users. Firstly, each user had to perform individual tasks. Afterward, users were matched and the application was used in competitive mode. This was done to assess the accuracy and speed of selection. On the other hand, qualitative data on satisfaction and usability were collected through questionnaires.

Results: The average accuracy achieved was 93.74% ± 1.71%, using 5.25 seconds per selection. The questionnaires showed that users felt a minimal workload. Likewise, high satisfaction values were obtained, highlighting that the application was intuitive and responds quickly and smoothly.