Let's do our thing and maybe there will be a revolution

Great discoveries, bold theories, scientific breakthroughs. The media is full of such formulations, usually exaggerated. Somewhere in the shadow of "great physics", the LHC, fundamental cosmological questions and the fight against the Standard Model, hardworking researchers are silently doing their job, thinking about practical applications and expanding the field of our knowledge step by step.

"Let's do our own thing" can certainly be the slogan of scientists involved in the development of thermonuclear fusion. For, despite the great answers to the big questions, the solution of practical, seemingly insignificant problems associated with this process, is capable of revolutionizing the world.

Perhaps, for example, it will be possible to do small-scale nuclear fusion - with equipment that fits on a table. Scientists at the University of Washington built the device last year Z-pinch (1), which is capable of maintaining a fusion reaction within 5 microseconds, although the main impressive information was the miniaturization of the reactor, which is only 1,5 m long. The Z-pinch works by trapping and compressing the plasma in a powerful magnetic field.

Not very effective, but potentially extremely important efforts to . According to research by the US Department of Energy (DOE), published in October 2018 in the journal Physics of Plasmas, fusion reactors have the ability to control plasma oscillation. These waves push high-energy particles out of the reaction zone, taking with them some of the energy needed for the fusion reaction. A new DOE study describes sophisticated computer simulations that can track and predict wave formation, giving physicists the ability to prevent the process and keep particles under control. Scientists hope their work will help in construction ITER, perhaps the most famous experimental fusion reactor project in France.

Also achievements such as plasma temperature 100 million degrees Celsius, obtained at the end of last year by a team of scientists at the China Institute of Plasma Physics in the Experimental Advanced Superconducting Tokamak (EAST), is an example of a step-by-step progress towards efficient fusion. According to experts commenting on the study, it may be of key importance in the aforementioned ITER project, in which China participates along with 35 other countries.

Superconductors and electronics

Another area with great potential, where rather small, painstaking steps are being taken instead of big breakthroughs, is the search for high-temperature superconductors. (2). Unfortunately, there are a lot of false alarms and premature worries. Usually rave media reports turn out to be exaggerations or simply untrue. Even in more serious reports there is always a “but”. As in a recent report, scientists at the University of Chicago have discovered superconductivity, the ability to conduct electricity without loss at the highest temperatures ever recorded. Using cutting-edge technology at the Argonne National Laboratory, a team of local scientists studied a class of materials in which they observed superconductivity at temperatures around -23°C. This is a jump of about 50 degrees from the previous confirmed record.

2. Superconductor in a magnetic field

The catch, however, is that you have to apply a lot of pressure. The materials that were tested were hydrides. For some time, lanthanum perhydride has been of particular interest. In experiments, it was found that extremely thin samples of this material exhibit superconductivity under the action of pressures in the range from 150 to 170 gigapascals. The results were published in May in the journal Nature, co-authored by Prof. Vitaly Prokopenko and Eran Greenberg.

To think about the practical application of these materials, you will have to lower the pressure and also the temperature, because even down to -23 ° C is not very practical. Work on it is typical small step physics, going on for years in laboratories around the world.

The same applies to applied research. magnetic phenomena in electronics. More recently, using highly sensitive magnetic probes, an international team of scientists has found surprising evidence that the magnetism that occurs at the interface of thin layers of non-magnetic oxide can be easily controlled by applying small mechanical forces. The discovery, announced last December in Nature Physics, shows a new and unexpected way to control magnetism, theoretically allowing for thinking about denser magnetic memory and spintronics, for example.

This discovery creates a new opportunity for miniaturization of magnetic memory cells, which today already have a size of several tens of nanometers, but their further miniaturization using known technologies is difficult. Oxide interfaces combine a number of interesting physical phenomena such as two-dimensional conductivity and superconductivity. The control of current by means of magnetism is a very promising field in electronics. Finding materials with the right properties, yet affordable and cheap, would allow us to get serious about developing spintronic.

it's tiring too waste heat control in electronics. UC Berkeley engineers have recently developed a thin-film material (film thickness 50-100 nanometers) that can be used to recover waste heat to generate power at levels never seen before in this type of technology. It uses a process called pyroelectric power conversion, which new engineering research shows is well-suited for use in heat sources below 100°C. This is just one of the latest examples of research in this area. There are hundreds or even thousands of research programs around the world related to energy management in electronics.

"I don't know why, but it works"

Experimenting with new materials, their phase transitions and topological phenomena is a very promising area of ​​research, not very efficient, difficult and rarely attractive to the media. This is one of the most frequently cited research in the field of physics, although it received a lot of publicity in the media, the so-called. mainstream they usually don't win.

Experiments with phase transformations in materials sometimes bring unexpected results, for example metal smelting with high melting points room temperature. An example is the recent achievement of melting gold samples, which typically melt at 1064°C at room temperature, using an electric field and an electron microscope. This change was reversible because turning off the electric field could solidify the gold again. Thus, the electric field has joined the known factors influencing phase transformations, in addition to temperature and pressure.

Phase changes were also observed during intense pulses of laser light. The results of the study of this phenomenon were published in the summer of 2019 in the journal Nature Physics. The international team to achieve this was led by Nuh Gedik (3), professor of physics at the Massachusetts Institute of Technology. The scientists found that during optically induced melting, the phase transition occurs through the formation of singularities in the material, known as topological defects, which in turn affect the resulting electron and lattice dynamics in the material. These topological defects, as Gedik explained in his publication, are analogous to tiny vortices that occur in liquids such as water.

For their research, scientists used a compound of lanthanum and tellurium LaTe.₃. The researchers explain that the next step will be to try to determine how they can "generate these defects in a controlled manner." Potentially, this could be used for data storage, where light pulses would be used to write or repair defects in the system, which would correspond to data operations.

And since we got to ultrafast laser pulses, their use in many interesting experiments and potentially promising applications in practice is a topic that often appears in scientific reports. For example, the group of Ignacio Franco, assistant professor of chemistry and physics at the University of Rochester, recently showed how ultrafast laser pulses can be used to distorting properties of matter Oraz electric current generation at a speed faster than any technique known to us so far. The researchers treated thin glass filaments with a duration of one millionth of a billionth of a second. In the blink of an eye, the glassy material turned into something like a metal that conducts electricity. This happened faster than in any known system in the absence of an applied voltage. The direction of the flow and the intensity of the current can be controlled by changing the properties of the laser beam. And since it can be controlled, every electronics engineer looks with interest.

Franco explained in a publication in Nature Communications.

The physical nature of these phenomena is not fully understood. Franco himself suspects that mechanisms like stark effect, i.e., the correlation of the emission or absorption of light quanta with an electric field. If it were possible to build working electronic systems based on these phenomena, we would have another episode of the engineering series called We Don't Know Why, But It Works.

Sensitivity and small size

Gyroscopes are devices that help vehicles, drones, as well as electronic utilities and portable devices navigate in three-dimensional space. Now they are widely used in devices that we use every day. Initially, gyroscopes were a set of nested wheels, each of which rotated around its own axis. Today, in mobile phones, we find microelectromechanical sensors (MEMS) that measure changes in forces acting on two identical masses, oscillating and moving in the opposite direction.

MEMS gyroscopes have significant sensitivity limitations. So it's building optical gyroscopes, with no moving parts, for the same tasks that use a phenomenon called Sagnac effect. However, until now there was a problem of their miniaturization. The smallest high performance optical gyroscopes available are larger than a ping pong ball and not suitable for many portable applications. However, engineers at the Caltech University of Technology, led by Ali Hadjimiri, have developed a new optical gyroscope that five hundred times lesswhat is known so far4). He enhances his sensitivity through the use of a new technique called "mutual reinforcement» Between two beams of light that are used in a typical Sagnac interferometer. The new device was described in an article published in Nature Photonics last November.

4. Optical gyroscope developed by Ali Hadjimiri and his colleagues. 

The development of an accurate optical gyroscope can greatly improve the orientation of smartphones. In turn, it was built by scientists from Columbia Engineering. first flat lens capable of correctly focusing a wide range of colors at the same point without the need for additional elements may affect the photographic capabilities of mobile equipment. The revolutionary micron-thin flat lens is significantly thinner than a sheet of paper and delivers performance comparable to premium composite lenses. The group's findings, led by Nanfang Yu, an assistant professor of applied physics, are presented in a study published in the journal Nature.

Scientists have built flat lenses from "metaatoms". Each metaatom is a fraction of a wavelength of light in size and delays light waves by a different amount. By building a very thin flat layer of nanostructures on a substrate as thick as a human hair, the scientists were able to achieve the same functionality as a much thicker and heavier conventional lens system. Metalenses can replace bulky lens systems in the same way that flat screen TVs have replaced CRT TVs.

Why a big collider when there are other ways

The physics of small steps can also have different meanings and meanings. For example - rather than building monstrously large type structures and demanding even larger ones, as many physicists do, one can try to find answers to big questions with more modest tools.

Most accelerators accelerate particle beams by generating electric and magnetic fields. However, for some time he experimented with a different technique - plasma accelerators, acceleration of charged particles such as electrons, positrons and ions using an electric field combined with a wave generated in an electron plasma. Lately I've been working on their new version. The AWAKE team at CERN uses protons (not electrons) to create a plasma wave. Switching to protons can take particles to higher energy levels in a single step of acceleration. Other forms of plasma awakening field acceleration require several steps to reach the same energy level. Scientists believe their proton-based technology could enable us to build smaller, cheaper, and more powerful accelerators in the future.

5. Two-stage miniature accelerator from DESY - visualization

In turn, scientists from DESY (short for Deutsches Elektronen-Synchrotron - German electronic synchrotron) set a new record in the field of miniaturization of particle accelerators in July. The terahertz accelerator more than doubled the energy of the injected electrons (5). At the same time, the setup significantly improved the quality of the electron beam compared to previous experiments with this technique.

Franz Kärtner, head of the ultrafast optics and X-ray group at DESY, explained in a press release. -

The associated device produced an accelerating field with a maximum intensity of 200 million volts per meter (MV/m) - akin to the most powerful modern conventional accelerator.

In turn, a new, relatively small detector ALPHA-g (6), built by the Canadian company TRIUMF and shipped to CERN earlier this year, has the task of measure the gravitational acceleration of antimatter. Does antimatter accelerate in the presence of a gravitational field on the Earth's surface by +9,8 m/s2 (down), by -9,8 m/s2 (up), by 0 m/s2 (no gravitational acceleration at all), or has some other value ? The latter possibility would revolutionize physics. A small ALPHA-g apparatus can, in addition to proving the existence of "anti-gravity", lead us on a path leading to the greatest mysteries of the universe.

On an even smaller scale, we are trying to study phenomena of an even lower level. Above 60 billion revolutions per second it can be designed by scientists from Purdue University and Chinese universities. According to the authors of the experiment in an article published a few months ago in Physical Review Letters, such a rapidly rotating creation will allow them to better understand Secrets .

The object, which is in the same extreme rotation, is a nanoparticle about 170 nanometers wide and 320 nanometers long, which the scientists synthesized from silica. The research team levitated an object in a vacuum using a laser, which then pulsed it at a tremendous speed. The next step will be to conduct experiments with even higher rotational speeds, which will allow accurate research of basic physical theories, including exotic forms of friction in a vacuum. As you can see, you don't need to build kilometers of pipes and giant detectors to face fundamental mysteries.

In 2009, scientists managed to create a special kind of black hole in the laboratory that absorbs sound. Since then these sound  proved to be useful as laboratory analogues of the light-absorbing object. In a paper published in the journal Nature this July, researchers at the Technion Israel Institute of Technology describe how they created a sonic black hole and measured its Hawking radiation temperature. These measurements were in line with the temperature predicted by Hawking. Thus, it seems that it is not necessary to make an expedition to a black hole in order to explore it.

Who knows if hidden in these seemingly less efficient scientific projects, in painstaking laboratory efforts and repeated experiments to test small, fragmented theories, are the answers to the biggest questions. The history of science teaches that this can happen.