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Mechanical inputs boost diamond quantum sensor states as Q factor tops one million

Most people think of diamonds as high-end adornments. Not Ania Bleszynski Jayich. The UC Santa Barbara physicist sees diamonds, which she grows in the UC Quantum Foundry, as a potentially powerful foundation for quantum sensors. Sensors are currently much farther along in their development than other potential quantum applications. Diamond sensors are particularly promising because diamonds require relatively few quantum bits (qubits) to operate, whereas a quantum computer, for instance, requires more than 100,000, perhaps as many as a million, qubits to handle error correction, one of the main hurdles for quantum computing.

A paper about the latest advance from the Bleszynski Jayich lab, “Spin-embedded diamond optomechanical resonator with a mechanical quality factor exceeding one million,” has been published in the journal Optica.

Quantum ground state of rotation achieved for the first time in two dimensions

Quantum mechanics tells us that a particle can never be perfectly still. But how precisely can it be oriented? A research team at the University of Vienna, together with colleagues at TU Wien and Ulm University, has now cooled the rotational motion of a levitated silica nanorotor all the way to its quantum ground state—in two orientational degrees of freedom.

Reporting in Nature Physics, they show how optical cooling confines the nanoparticle’s orientation to within the bounds of quantum zero-point fluctuations, the unavoidable orientational uncertainty imposed by Heisenberg’s uncertainty principle. Such quantum-limited alignment is an important milestone towards rotational matter-wave interferometry and ultra-sensitive quantum torque sensing.

New detector triples the speed of electron camera, enabling higher sensitivity

An instrument that uses high-energy electrons to take “snapshots” of ultrafast chemical processes at the atomic and molecular level just got a major upgrade. Researchers have conducted the first experiment using a new detector, installed in the megaelectronvolt ultrafast electron diffraction (MeV-UED) instrument, at the Linac Coherent Light Source (LCLS) at the Department of Energy’s SLAC National Accelerator Laboratory.

This detector is the first to keep pace with the MeV-UED’s maximum electron production rate of 1,080 electron pulses per second. Compared to the previous detector’s maximum rate, the new detector collects three times more data over the same time span, drastically improving the instrument’s efficiency and sensitivity.

“With this new detector, we’re able to read out each individual pulse of electrons from the instrument,” said Alexander Reid, MeV-UED facility director. “That gives us a much more powerful way of examining the experimental data to answer our science questions.”

$220 Billion Problem: Scientists Uncover the Secret Weapon Bacteria Use To Take Over Crops

Plant-infecting bacteria have a surprisingly direct way of taking over crops. Instead of slowly breaking down defenses, many of them inject proteins straight into plant cells, effectively hijacking the system from the inside.

For decades, scientists have tried to understand one particularly important group of these proteins, known as AvrE/DspE. These molecules are used by pathogens that attack a wide range of crops, including rice, tomatoes, apples, and pears. They are responsible for diseases such as bacterial speck, brown spot, and the devastating fire blight that can wipe out entire orchards.

Physicists Found Something That Can Move Faster Than Light: The Darkness Inside It

For the first time, physicists have observed that ‘holes’ in light can move faster than the light itself.

They’re known as phase singularities or optical vortices, and since the 1970s, scientists have predicted that, just as eddies in a river can move faster than the flowing water around them, so too can whirlpools in a wave of light outrun the light they’re embedded within.

This does not break relativity, which states that nothing can travel faster than the speed of light. That’s because the vortices carry no mass, energy, or information, and their motion is based on the evolving geometry of the wave pattern rather than any physical motion through space.

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