(사진 제공: 과학동아)
“The bottom side that we see through the gap in the floor seems quite distant, does it not? The bottom is almost 4 meters away from the floor that we are standing on.”
Eyes filled with curiosity all stared at the floor of the laboratory when Dr. Wonjun Jang explained at the Center for Quantum Nanoscience (QNS) of the Institute of Basic Sciences (IBS). On a snowy day on January 26th, the Lab tour was held at QNS located at Ewha Womans University. It was a special event that was planned in line with the special January edition of Science Donga, “Quantum Mechanic Teleport”. 10 readers of Science Donga who participated in the lab tour had a chance to talk to the researcher during their visit to QNS which they only read about in the magazine.
The lab tour opened with the lecture provided by Dr. Jang, “Contemplation on Quantum Computing”. The seminar room flooded with questions from the readers once the lecture by Dr. Jang was finished. He encompassed a broad range of topics from quantum characteristics and quantum entanglement to quantum computing. Recently, we have often heard of the terminology, quantum, as the spotlight was on topics such as quantum computing and quantum communication. However, quantum nanoscience is still an unfamiliar field that is hard to understand for the general public. A reader, Ok Ye-eun, reflected, “I enjoyed the session because it was much easier to understand quantum nanoscience by listening to the explanation by a researcher.”
We tend to imagine a rigid space with an array of complex devices when we think of a laboratory. However, the laboratory the readers visited on this day was different from what we imagined. Images of quantum such as atoms or molecules were hanging on the wall. These pictures were taken by QNS researchers through the Scanning Tunneling Microscope (STM). Readers left memories of the day by taking “selfies” in front of the image of the movie Antman’s hero flying on top of a picture of atoms that was taken by an STM.
“From here, we will enter a building that was built with great care to minimize vibration. You see how there are soft mats on the floor, right? It seems like the spaces are connected, but in truth, this lab building is completely separated from the next building over these mats.”
Dr. Jang guided the readers into the laboratory building. This special building was designed to reduce vibration because the experiment equipment and STMs in the building are very sensitive.
STM observes nanomaterials samples using a sharp tip. For this, the tip has to move while keeping a 1nm (nanometer∙1nm equals 1/1 billion meters) distance away from the nanomaterial sample. The tip interacts electrically with the sample by applied voltage when they are extremely close to each other. STM uses this interaction to observe the characteristics of the sample or to manipulate them. Since it is important to maintain the 1nm distance, even a small amount of vibration cannot be accepted.
The lab also has a facility to reduce vibration. This is achieved by making the STM float in the air by 1 cm using four air springs. Because of this, there is a square-shaped gap surrounding the STM on the floor of the laboratory. The readers directly experienced the difference in the vibration by having one foot on the STM side and one foot on the outside with the gap in the middle. Many shouted, “I feel dizzy!” “I feel sick!” all over the room.
The last agenda that excited the readers as much as the amusing view of the laboratory was lunch with Director Andreas Heinrich of QNS. Readers got to know Director Heinrich better through lunch and after the lab tour, one reader left the center with an ambitious goodbye saying, “I will return (as a researcher) 10 years later. Please wait for me.”
‘Scientist who made the world’s smallest movie’. This is one of the nicknames of Andreas Heinrich at the Center for Quantum Nanoscience (QNS) of the Institute of Basic Sciences (IBS). The movie that he made in 2013 while working at IBM, called “A Boy and His Atom” was literally made by “atoms”. The foot of the boy was drawn by arranging three carbon monoxide molecules side by side in an array. I visited QNS on January 19th to meet with the very person who produced a movie that runs for about a minute by moving molecules in a very delicate manner.
One question that I was most curious about was “Why?”. I thought there would have been a special reason for the scientist to create such content for the public by taking the time and effort. Director Heinrich said, “The most important reason is to open up the eyes of people,” and added, “people can feel the real existence of atoms when we show the atom to them.” In addition, he said, “This experience creates an enormously important opportunity for people.”
He also very welcomed the Science Donga readers for the lab tour. Director Henrich said, “A research center must return the accomplishments to the society that allowed science to be experienced,” and added, “I believe the lab tour on January 26th with readers of Science Donga will be an enjoyable time for me as well.”
The key research area of Director Heinrich is to determine the properties and movements of individual atoms and molecules using the Scanning Tunneling Microscope (STM). In particular, research using the Electron Spin Resonance STM (ESR-STM) that can control individual atoms of molecules on the surface using the magnetic field is the research topic newly pioneered by Director Heinrich when he was working at IBM. He said, “A new world to manipulate the location of atoms or molecules with a high-level accuracy and create and measure an arbitrary quantum state has been opened up through such a method of experiment,” and added, “Nevertheless, there is so much more to discover.”
A series of unknown things flood out every time a research project is carried out. When the journalist asked Director Heinrich whether he feels lost at times as if he is navigating through a vast open ocean, Director Heinrich smiled and answered, “There are three perspectives in science and engineering.”
The first perspective is having a solid target. It is one with very specific targets, such as having a better smartphone and a better television. The second perspective could be also set to resolve a broader issue, such as creating a better battery technology and a better AI algorithm.
The last perspective involves people who simply aim to experience a new phenomenon. Director Henrich expressed it as “exploring the vast ocean”. To him, science is a new possibility rather than a sense of loss, just like the undiscovered possibility that a vast ocean might have.
“My research (that uses STM) is like the development of a telescope for a ship that is navigating the ocean. A new continent that was not discovered before can be discovered if a better telescope is developed. It is likewise. Newer fields will be found if we develop equipment that is a million times more sophisticated than the existing equipment.”
His “development of a new telescope” is continuing in Korea as well. New research results emerged over the past 5 years, ever since he built a new team and started research at QNS. One of the main achievements was succeeding in taking a magnetic resonance image (MRI) of a single atom. Director Heinrich said, “Improving the ESR-STM that was made previously in IBM and enabling a faster observation here at QNS is also a big accomplishment,” and added, “The state of atoms or molecules can be observed a million times faster than the existing equipment.” He explained, “It is an advancement similar to a camera that was only used to take photos before, but now can take videos.” Such accomplishments were acknowledged, and Max Planck Institute in Germany, his home country, awarded him with the Humboldt Prize on February 6th, introducing Director Heinrich as “the pioneer of the field of quantum spins on surfaces”. Humboldt Prize is an award that is given annually to scholars who make world-class accomplishments in the field of natural sciences and humanities and social sciences.
“The goal for the past 5 years was to ensure that QNS grows as a world-class research center. We were very successful. The goal for the next 5 years is to achieve world-class science in this facility. This is because we are explorers. Until now, we could only deal with a single qubit (qubit∙basic unit of quantum computing). In QNS, we are working on using single atoms or molecules as qubits. We will be able to flexibly manipulate even more qubits in the future. Moreover, another goal is to create STM that can manipulate individual particles with light, and not magnetic fields.”
(사진 제공: 과학동아)
(사진 제공: 과학동아)