microwave signal

A microwave oven heats food, but in the lab, microwaves have done something different: they turned a superconductor into a permanent magnet. A 300-nanometer-thick film of yttrium barium copper oxide, cooled to 80 kelvin, responded to 5-gigahertz radiation.

A quantum lab is like a kitchen where the chef waits a day for the stove to cool down. Superconducting qubits only work at temperatures of a few hundredths of a kelvin, and each 'cool, measure, warm up' cycle eats a whole day. A team of engineers built a fridge the size of a melon, weighing 3 kg, that does the job in just two hours.

An ordinary flashlight shines in all directions, and after just a couple of dozen meters its beam fades so much it barely lights a wall. The atmosphere scatters light, and wind and heat currents distort it even more. But if you lay an invisible pipe for light right in the air, the beam will travel through it like water through a hose.

A radio receiver the size of a palm can measure signal power more accurately than expensive lab benches. Inside, there are no coils or antennas, just a glass head and a cloud of rubidium atoms cooled to near absolute zero.

At the end of a massive star's life, its core collapses in a fraction of a second, giving birth to a supernova flash. This cataclysm shakes spacetime itself, emitting gravitational waves — ripples that race across the Universe.

In a dark room, a whisper is barely audible. To make out the words, you need to get close, or set up many sensitive microphones. That's roughly the reasoning behind the new work: the authors place quantum "ears" right inside a resonator, where a high-frequency gravitational wave turns into an electromagnetic echo.

You could send a short radio pulse toward a black hole and wait for the reflected echo. Intuitively, the shorter the signal, the better it would probe the finest details of spacetime right at the horizon: that region from which even light cannot return.

In the first moments after the Big Bang, the Universe hummed like a bell. Inflation, the epoch of rapid expansion confirmed by measurements of the cosmic microwave background, ended, and the inflaton field began oscillating around the minimum of its potential.

A typical laser is a cavity where light bounces between mirrors and gets amplified. But you can ditch the mirrors and make light circulate inside a tiny particle smaller than the light wave itself. That's how the new lasers work: nanoparticles of indium phosphide sitting on perfectly smooth gold.

The planet-spanning web of undersea internet cables acts like a giant ear. The glass thread inside responds to water movements: currents, tides, and distant earthquakes bend the cable. Light traveling along the thread takes slightly longer: this delay is measured on shore against a reference. That’s how the speed of light reveals itself.

A lighthouse sends its beam through a storm of its own mirrors: that's roughly how fast radio bursts behave when trying to leave a magnetar's vicinity. A magnetar is a neutron star with a magnetic field a quadrillion times stronger than Earth's.

A quantum computer is like an orchestra where every musician-qubit must play in perfect silence. But when you have many such orchestras that want to perform together, they need a reliable conductor-communicator.

An ultra-sensitive microphone tries to catch the whisper of a distant galaxy. But the microphone itself trembles from heat: its atoms jitter like popcorn in a pan. Physicists call this jitter thermal noise, and it often drowns out weak signals.

An ordinary laser emits narrow lines, like a string that sounds only one note. For spectroscopy, this is inconvenient: if a substance absorbs light between the lines, you might miss it.

A quantum memory node is a tiny diamond with a defect that can store and emit single photons. But its light has a wavelength of 637 nanometers, the same red as a ruby, and is almost completely absorbed after just a few meters of standard optical fiber.

An ordinary camera flash lingers for hundredths of a second, but for atoms, that's an eternity. Inside molecules, electrons jump in attoseconds: billionths of a billionth of a second. To capture that, you need a light pulse shorter than the event itself. Physicists take an electron beam in a linear accelerator and compress it so that individual bunches become thinner than a hair — in time.

An ordinary camera captures light reflected from objects and builds a picture from it. But if the object is hidden behind an obstacle or does not reflect light, radio waves come to the rescue: they pass through walls and fog, and a computer reconstructs the image from scattered signals.

A neuron perceives electrical signals like an ultrasensitive microphone picking up the faintest vibrations.

Quantum computers and sensors operate at microwave frequencies, but transmitting their signals over long distances is conveniently done via optical fibers, which use light.

Ordinary soldering doesn't work for quantum circuits: when cooled to liquid helium temperatures, metal cracks, and the contacts themselves introduce noise. Engineers from the research group tried something different — a drop of gallium alloy that stays liquid at room temperature, like mercury in an old thermometer.

A quantum computer in the lab resembles an orchestra: lasers play the role of bows, and ions are the strings. To play the desired melody, powerful radio signals are sent to the lasers: they set the rhythm and pitch. But part of this "music" escapes the stage.

Sound on a crystal surface is like ripples on water, but traveling through a solid. This ripple is called a surface acoustic wave: it moves a hundred thousand times slower than light, so it can be compressed into very short segments and fit on a tiny chip. Usually, such waves are launched by metallic combs made of aluminum or gold.

A quantum computer is like a finicky orchestra: each qubit is a musician who hears the slightest noise and loses their place. To play a complex symphony of computations, you need hundreds of instruments tuned in unison.

Gamma rays are the most energetic flashes of light born deep within atoms. Their energies are like fingerprints: each radioactive element has its own pattern. But measuring that pattern with high precision is like weighing a grain of sand on a scale sitting on a vibrating truck. The new setup works like an ultra-sensitive thermometer.

A thin film, clamped between two metal posts, trembles at the slightest nudge. Its movements are picked up by a microwave resonator — a cavity where radio waves bounce around like sound in an empty room. When the membrane shifts, the cavity's response changes.

The same explosion can sound different: it all depends on which way the wind is blowing. In 2024, researchers set off charges equivalent to ten tons of TNT twice and recorded the sound with a network of 31 microphones spread over a radius of 23 kilometers. The source was identical, but the acoustic pictures turned out to be quite different.

Ordinary light is a stream of photons flying every which way: sometimes more, sometimes fewer, and in that chaos, measurement precision gets lost. Physicists have learned to "tame" this stream by creating squeezed light — where the noise in one characteristic drops below the vacuum level.

Short gamma-ray bursts — instantaneous, but most powerful explosions — are born from the mergers of neutron stars (the superdense remnants of dead stars).

The solar wind isn't a calm stream but a bubbling soup of charged particles. Diving close to the Sun, the Parker probe picked up two types of stirring waves. Left-handed ones, like a whisk in a chef's hand, whip up the material when the temperature differs along and across the flow.

A tiny seesaw weighing 1.5 nanograms oscillates not from the wind, but from the heat of its surroundings. Physicists nearly stopped it by cooling it to 0.006 degrees above absolute zero.

In a dilution refrigerator cooled to 170 millikelvin, a coherent state of the microwave field is born. This is laser light with minimal uncertainty: its amplitude and phase are defined as precisely as quantum mechanics allows.

Two dilution cryostats, each the size of a barrel, stand at opposite ends of the laboratory. Inside are superconducting circuits cooled to 50 millikelvin, a hundred times colder than interstellar space. Between them runs an ordinary optical fiber, a kilometer of glass thread carrying light.

Picking up an ultraweak microwave signal is like trying to hear a whisper in a storm. Rydberg atoms, inflated to the size of bacteria, promise to become perfect antennas. But there's a fatal catch: during optical readout, up to 98% of messenger photons vanish without a trace in the detector.