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Scientists all over the world use modeling approaches to understand complex natural systems such as climate systems or neuronal or biochemical networks. A team of researchers has now developed a new mathematical framework that explains, for the first time, a mechanism behind long transient behaviors in complex systems.

This results in differences in the acoustic energy between the LC layers, glass disks, and the surrounding air, inducing an acoustic radiation force acting at the LC layer and glass disk boundary. This effect changes the molecular orientation of the LC layers, altering the transmitted light distribution. By changing the electrodes to which the is applied, the direction of the molecular orientation and therefore the diffusion directivity can be easily rotated.

The researchers investigated the diffusion characteristics of the device and found that the diffusion angle depends on the input voltage amplitude and is maximized at 16 V. Above this voltage amplitude, the diffused light can become unstable. Additionally, the transmitted light distribution depends on the polarization of incident light.

“Light diffusers that allow control over diffusion directivity can reduce and enable users to tune the light distribution to their taste, resulting in better aesthetics Our device marks the first report of an ultrasonically controllable optical diffuser based on LC material, providing users control over diffusion directivity within a small space,” said Prof. Koyama.

Scientists from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have created the first-ever atomic movies showing how atoms rearrange locally within a quantum material as it transitions from an insulator to a metal. With the help of these movies, the researchers discovered a new material phase that settles a yearslong scientific debate and could facilitate the design of new transitioning materials with commercial applications.

The formation of a black hole from light alone is permitted by general relativity, but a new study says quantum physics rules it out.

Black holes are known to form from large concentrations of mass, such as burned-out stars. But according to general relativity, they can also form from ultra-intense light. Theorists have speculated about this idea for decades. However, calculations by a team of researchers now suggest that light-induced black holes are not possible after all because quantum-mechanical effects cause too much leakage of energy for the collapse to proceed [1].

The extreme density of mass produced by a collapsed star can curve spacetime so severely that no light entering the region can escape. The formation of a black hole from light is possible according to general relativity because mass and energy are equivalent, so the energy in an electromagnetic field can also curve spacetime [2]. Putative electromagnetic black holes have become popularly known as kugelblitze, German for “ball lightning,” following the terminology used by Princeton University physicist John Wheeler in early studies of electromagnetically generated gravitational fields in the 1950s [3].

In most neutral-atom quantum computers, atoms are held in arrays of optical tweezers. Researchers typically populate the arrays stochastically, meaning that whether a given site receives an atom is down to chance. Atoms can later be rearranged individually, but the total number of atoms depends on the success of the initial loading.

The Atom Computing team developed an iterative process to fill an array to capacity. Instead of filling the array directly, the researchers first stochastically populated a second “reservoir” array. They then transferred atoms one by one from this reservoir to the target array using an optical tweezer. Between each loading step, the researchers imaged both arrays to determine which sites in each array were occupied. This step required temporarily switching off the tweezers and holding the atoms in an optical lattice formed from interfering laser beams.

The researchers showed that this sequence could be repeated as many times as necessary without losing atoms from the target array. They also showed that they could limit atom loss during the imaging step by enhancing the lattice strength using optical cavities. This enhancement allowed the atoms to be more strongly confined without increasing the optical lattice’s laser-power requirements.