Explore the quantum triad! Pan's team named to Physics World 2022 Top 10 Breakthroughs of the Year

 

On December 8, Physics World, the British Physical Society's news website, announced its Top 10 Breakthroughs of the Year 2022, which cover everything from quantum and medical physics to astronomy and condensed matter, including the team of Jianwei Pan, who has just published a paper creating ultracold polyatomic molecules.

 

The 10 breakthroughs were selected by a team of editors at Physics World: they sifted through hundreds of research updates in physics published on the Physics World website this year, and the 2022 Breakthrough of the Year award (1 of 10 chosen) will be officially announced on December 14 [1]. The following are the top 10 breakthroughs for 2022, in no particular order.

 

01Ushering in a new era of ultracold chemistry

 

 

Cooling light: the experimental setup used by Pan and colleagues

 

The first ultracold polyatomic molecule was created by scientists Jianwei Pan and Bo Zhao from the University of Science and Technology of China and the Chinese Academy of Sciences, and John Doyle from Harvard University in the U.S. On December 2, 2022, this research was published in the leading international academic journal Science [2].

 

Although physicists have been cooling atoms above absolute zero for more than 30 years, and the first ultracold diatomic molecules appeared in the mid-2000s, the goal of creating ultracold molecules containing three or more atoms has proved elusive.

 

Using different and complementary techniques, teams from the University of Science and Technology of China and Harvard University fabricated samples of triatomic sodium-potassium molecules at temperatures of 220 nK and 110 µK, respectively. Their achievement paves the way for new research in physics and chemistry, with studies of ultracold chemical reactions, new forms of quantum simulations, and tests of basic science all closer to realization. Thanks to these polyatomic molecular platforms, the study of ultracold chemical reactions, new forms of quantum simulations, and tests in basic science are much closer to realization.

 

 

Schematic diagram of the preparation of an ultracold triatomic molecular system by magnetic conjugation

 

In this study, the team has successfully prepared the first ultracold triatomic molecular complex with high phase space density by a slow scanning magnetic field in the vicinity of the Feshbach resonance of sodium-potassium molecules and potassium atoms, adiabatically transferring the sodium-potassium molecule-potassium atom scattering state to the triatomic molecule bound state, starting from a quantum-simplified mixture of sodium-potassium molecules and potassium atoms. atomic molecular systems with high phase space density. The team obtained the dissociation spectrum of triatomic molecules by dissociating the triatomic molecules into free sodium-potassium molecules and atoms using the RF dissociation technique, thus enabling the direct detection of triatomic molecules. The experimental results show that the phase space density of the obtained triatomic molecular gas is improved by about 10 orders of magnitude compared with other methods. The preparation of supercooled triatomic molecular systems paves the way to simulate the three-body problem under quantum mechanics, and the obtained high phase space density makes it possible to prepare Bose-Einstein condensation of triatomic molecules.

 

The reviewers agreed that this work is a milestone in the field of ultracold molecule research and opens up new directions for the study of ultracold chemistry and quantum simulations.

 

In addition to this year, Pan's team was also selected as one of Physics World's top 10 breakthroughs of the year in 2015, and won the final Breakthrough of the Year Award. At that time, Pan and Lu Chaoyang were selected for their work to achieve the first simultaneous transmission of two internal Bing properties of an elementary particle (photon), the first time that work done locally in China has won this award.

 

02Observation of four neutrons

 

Meytal Duer of the Institute of Nuclear Physics at the Technical University of Darmstadt, Germany, and members of the SAMURAI Collaboration have observed tetraneutrons and demonstrated the existence of uncharged nuclear matter, if only for a short period of time.

 

03Super-efficient power generation

 

Alina LaPotin, Asegun Henry and colleagues at the Massachusetts Institute of Technology and the National Renewable Energy Laboratory, constructed a thermophotovoltaic (TPV) cell with an efficiency of more than 40%.

 

04The Fastest Photovoltaic Switch

 

Marcus Ossiander, Martin Schultze and teams at the Max Planck Institute for Quantum Optics and the University of Munich, Germany, the Technical University of Vienna and the Technical University of Graz, Austria, and the CNR NANOTEC Institute of Nanotechnology, Italy, have defined and explored the "speed limit" of optoelectronic switches in physical devices ".

 

05Opening a new window on the universe

 

 

The nebula at the base of the ship as seen by JWST

 

After years of delays and rising costs, the $10 billion James Webb Space Telescope (JWST) will finally launch on Dec. 25, 2021. For many space probes, launch is the most dangerous part of the mission, but JWST must also endure a series of dangerous deep-space unpacking maneuvers, including unfolding its 6.5-meter primary mirror and unfolding its tennis-court-sized sunshade. The observatory is expected to remain operational until 2030 and has already begun to revolutionize astronomy.

 

06First human FLASH proton therapy

 

Emily Daugherty of the University of Cincinnati and collaborators working on the FAST-01 trial conducted the first clinical trial of FLASH radiation therapy and the first use of FLASH proton therapy in humans.

 

07Refining light transmission and absorption

 

A team led by Stefan Rotter of the Technical University of Vienna, Austria, and Matthieu Davy of the University of Rennes, France, has created an anti-reflective structure that enables perfect transmission in complex media; while a collaboration led by Rotter and Ori Katz of the Hebrew University of Jerusalem, Israel, has developed an " anti-laser" that allows any material to absorb all light from a wide range of angles.

 

08A new semiconductor: cubic boron arsenide

 

 

Ball-and-stick representation of cubic boron arsenide

 

An independent team led by Gang Chen of the Massachusetts Institute of Technology and Xinfeng Liu of the National Center for Nanoscience and Technology in Beijing, China, have demonstrated that cubic boron arsenide is one of the best semiconductors known to science.

 

09Changing the orbit of an asteroid

 

NASA and the Johns Hopkins Applied Physics Laboratory demonstrate the first "kinetic impact" by successfully altering the orbit of an asteroid.

 

10Detecting the Aharonov-Bohm Effect of Gravity

 

Chris Overstreet, Peter Asenbaum, Mark Kasevich and colleagues at Stanford University have detected the gravitational effect of Aharonov-Bohm.

 

The original Aharonov-Bohm effect, first predicted in 1949, is a quantum phenomenon in which the wave function of a charged particle is affected by an electric or magnetic potential, even if the particle is in a region of zero electric and magnetic fields. Since the 1960s, this effect has been observed by splitting a beam of electrons and sending two beams of electrons to either side of a region containing a completely shielded magnetic field. When these two beams of electrons recombine at a detector, the Aharonov-Bohm effect is shown as interference between the two beams of electrons.

 

Now, physicists at Stanford University have observed a gravitational version of this effect using ultracold atoms. The team divided the atoms into two groups, separated by about 25 centimeters, and one of the groups gravitationally interacted with a large-mass object. When recombined, the atoms showed a disturbance that was consistent with the gravitational force of the Aharonov-Bohm effect. This effect can be used to determine Newton's gravitational constant with very high accuracy.

 

Reference link：

[1]https://physicsworld.com/a/physics-world-reveals-its-top-10-breakthroughs-of-the-year-for-2022/

[2]www.science.org/doi/10.1126/science.ade6307