The 2023 Nobel Prize in Physics goes to physicists Pierre Agostini of Ohio State University, Ferenc Krausz of the Max Planck Institute for Quantum Optics, and Anne L’Huillier of Pierre and Marie Curie University, who developed tools to study electrons inside atoms and molecules. was given. This has been reported representatives The Nobel Committee at the ceremony in Stockholm.
“We have been waiting for this award for a long time, I am very sorry that Paul Corkum is not on the team – this is the great Canadian scientist who understood where the attosecond impulse comes from and discovered the reverse collision. So he made fundamental discoveries in this direction. But all scientists who received the award are very worthy of it,” Alexander Sergeev, head of the National Center for Physics and Mathematics, former president of the Russian Academy of Sciences, told socialbites.ca.
Who can quickly turn on the light?
In the world of electrons, changes occur in an extremely short period of time; attoone-tenth of a second, that is, one quintillionth of a second, or 0.000000000000000001 second.
Current methods for recording changes in electrons are not sufficient. The prize winners succeeded in creating a way to produce extremely short pulses of light that can be used to observe the movement of electrons in atoms or molecules in real time. It plays an important role in understanding general physical phenomena or chemical reactions at the atomic level. Such attosecond pulses could be used to create a type of video camera to record movies inside atoms and molecules in mega-slow motion.
“All processes in the world definitely start with electronic transition. This is the holy grail by which we can control the start time of a molecular reaction and therefore control the reactions themselves in the future,” said Anne L’Huillier during the invocation at the ceremony where the results were announced.
However, in order to make such a film, the principle of how to illuminate the atoms in the molecules and how to learn how to turn the light on and off so quickly had to be revealed.
“The difficulty is that neither humans, nor mechanics, nor electronic devices have the speed to turn light on and off that quickly. This requires specific devices. And even the electronics that existed before the work of the Nobel laureates could not provide the required pulse duration for such short flashes of light.” A new principle was needed to produce it. Powerful lasers capable of ionizing atoms came to our rescue,” Mikhail Ryabikin, a leading employee of the Institute of Applied Physics of the Russian Academy of Sciences (Nizhny Novgorod), told socialbites.ca.
To take a photo of a motorcyclist and film blur-free movements, you need to use a very high shutter speed. This is the achievement of Nobel laureates. You can now illuminate the material with flashes and take a picture of the electron. Or you can start a chemical reaction, making a movie about the movement of electrons. This is done using attosecond lasers.
How is it applied?
One application is to create new electrical conductors. With the help of attosecond lasers, it was possible to detect how a substance in an insulator becomes conductive for a short time and then becomes conductive again.
“For example, if you send a short laser pulse onto silicon, it changes from a dielectric to a conductor. When the pulse ends, a return to the opposite state occurs. We would never know this without the technology. This can be used to speed up the operation of computers; we can build a memory cell on top of it,” Ryabikin said.
If you know how an electron moves from one end of the molecule to the other, you can control the chemical reaction with the help of the new information. Flashes of light can be used to direct electrons to desired locations in the molecule. In this way the performance of solar panels can be significantly increased.
Many scientific groups in Russia are working on these problems; one of them is located at the Institute of Applied Physics of the Russian Academy of Sciences.
“We have studied different options for obtaining attosecond pulses: how to achieve them with higher efficiency, intensity, with a specific electric field profile and polarization. We are learning how to control the properties of these flashes of light and how to use them. For example, there are light-triggered photocells, followed by photoionization , a free electron and current emerge. No one knew how fast these photocells worked, how fast this photocurrent appeared. These pulses will make it possible to record with an accuracy of 20 attoseconds how long it takes for an electron to leave the atom and escape. Now this is the photoelectric effect we can measure time,” Ryabikin explains.
Attosecond pulses can also be used to identify various molecules in the diagnosis of various diseases such as lung cancer.
However, according to Moscow State University professor and physicist Andrei Vasiliev, this technology is still a matter of research and, unfortunately, it is too early to talk about its practical application in any field.
“This is a research and exotic technique, so it has no direct application yet. It is based on the impact of short pulses of light on a substance, which then enters a highly excited state. This method will help study how electrons are excited in complex molecular systems and how they change.” “You can find out how electrons move by indirectly comparing the resulting images. But it is too early to talk about practical application,” Vasiliev told socialbites.ca.
However, attosecond lasers can already be used in research. This is the study of any chemical and biological process in materials science, any field where you need to know something about the dynamics of electrons and how they behave in different situations.
Scientific life of award winners
Parisian Anne L’Huillier became the fifth woman to win the Nobel Prize in Physics. Before that, the award was awarded to Maria Skłodowska-Curie (1903), Maria Geppert-Mayer (1963), Donna Strickland (2018) and Andrea Mia Ghez (2020).
“This is really awesome. I was teaching when he called me, so it was only the third or fourth time I answered the phone. After learning about the award, the last half hour of the lesson was very difficult for me. “I don’t know how to speak nicely, partly because I was so touched by this news” – said L’Huillier when he learned that he was a Nobel laureate.
This is not her only accolade: In 2022, L’Huillier received the Wolf Prize in Physics, becoming the second woman in history to win this prize. The first of these was Chinese American physicist Wu Jianxiong in 1978.
“I think it’s time for women to receive more awards like this. I have provided support and mentorship to women throughout my career, especially over the last decade. I think this kind of help is important because women are more vulnerable than men in the field of physics. “Thank God, I see that these problems have been solved,” he said. tells Ann in an interview with the scientific journal Physics.
According to the scientist, he was inspired to study high-speed physics by teachers in his master’s program, including Nobel Prize winner in Physics Claude Cohen-Tannoudji.
L’Huillier currently works at Lund University in Sweden. He leads the attosecond physics group, which studies the real-time movement of electrons, used to understand chemical reactions at the atomic level. In 2003, he and his team broke the world record with the smallest laser pulse of 170 attoseconds.
Another award winner, Pierre Agostini, was also born in France. In 1968, the scientist received his doctorate from the University of Aix-Marseille. He later became a researcher at the Paris-Saclay Center of the French Alternative Energy and Atomic Energy Commission (CEA) and held various positions until 2002. He later worked as a visiting scholar at the University of Southern California, and in 2005 Agostini accepted a position as professor of physics at Ohio State University.
In 2001, Agostini was able to generate and study a series of consecutive light pulses, with each pulse lasting only 250 attoseconds. In 2012, he was part of a team of scientists from the universities of Ohio and Kansas that became the first to capture the movement of atoms within a molecule using an ultrafast camera. He also invented the RABBITT method to characterize attosecond light pulses.
Another award winner, Ferenc Krausz, was born in Hungary. He graduated from the Budapest University of Technology and remained there as a professor for many years, after which in 2003 he was appointed director of the Max Planck Institute for Quantum Optics in Garching (Germany).
Krausz and his research team were the first to create and measure an attosecond light pulse. This marked the beginning of attosecond physics.
In 2008, Krausz and colleagues at the Max Planck Institute for Quantum Optics hit The world’s shortest flash of light entered the Guinness Book of Records. The pulse of light they produced lasted only 80 attoseconds, or 0.00000000000000008 seconds.
In February 2022, Professor Krausz received the prestigious Wolf Prize in Physics for his pioneering contributions to ultrafast laser science and attosecond physics. He donated a cash prize of $100,000 to the charity he founded, Science4People.
“The fast shutter speed camera is the closest familiar analogy to the fundamental concept of attosecond physics. A fast shutter speed allows you to take clear photographs of fast-moving subjects by ensuring that the camera’s sensor is exposed to the outside world for only a short time. However, it is the world’s fastest shutter speed that can freeze the motion of a bullet.” “Even the microsecond exposure time of its fast camera is billions of times slower to capture electronic movements inside atoms, molecules or nanocircuits.” said Professor Krausch told iGlobeNews about his research.
He is confident that studying and controlling the motion of electrons in the future will make it possible to bring the speed of information processing to the speed of light.