UNB, Dhaka :
An international team, led by a Bangladeshi scientist of Princeton University, has discovered an elusive massless particle theorised 85 years ago.
The particle could give a rise to faster and more efficient electronics because of its unusual ability to behave as matter and antimatter inside a crystal, according to new research.
The researchers report in the journal Science July 16 the first observation of Weyl fermions, which, if applied to next-generation electronics, could allow for a nearly free and efficient flow of electricity in electronics, and thus greater power, especially for computers, the researchers suggest.
Proposed by the mathematician and physicist Hermann Weyl in 1929, Weyl fermions have been long sought by scientists because they have been regarded as possible building blocks of other subatomic particles, and are even more basic than the ubiquitous, negative-charge carrying electron (when electrons are moving inside a crystal).
Their basic nature means that Weyl fermions could provide a much more stable and efficient transport of particles than electrons, which are the principle particle behind modern electronics.
Unlike electrons, Weyl fermions are massless and possess a high degree of mobility; the particle’s spin is both in the same direction as its motion – which is known as being right-handed – and in the opposite direction in which it moves, or left-handed.
“The physics of the Weyl fermion are so strange, there could be many things that arise from this
particle that we’re just not capable of imagining now,” said corresponding author M. Zahid Hasan, a Princeton professor of physics who led the research team.
The team included numerous researchers from Princeton’s Department of Physics, including (from left to right) graduate students Ilya Belopolski and Daniel Sanchez; Guang Bian, a postdoctoral research associate; corresponding author M Zahid Hasan, a Princeton professor of physics who led the research team; and associate research scholar Hao Zheng.
The researchers’ find differs from the other particle discoveries in that the Weyl fermion can be reproduced and potentially applied, Hasan said.
Typically, particles such as the famous Higgs boson are detected in the fleeting aftermath of particle collisions, he said.
The Weyl fermion, however, was discovered inside a synthetic metallic crystal called tantalum arsenide that the Princeton researchers designed in collaboration with researchers at the Collaborative Innovation Center of Quantum Matter in Beijing and at National Taiwan University.
The Weyl fermion possesses two characteristics that could make its discovery a boon for future electronics, including the development of the highly prized field of efficient quantum computing, Hasan explained.
For a physicist, the Weyl fermions are most notable for behaving like a composite of monopole- and antimonopole-like particles when inside a crystal, Hasan said.
This means that Weyl particles that have opposite magnetic-like charges can nonetheless move independently of one another with a high degree of mobility.
The researchers also found that Weyl fermions can be used to create massless electrons that move very quickly with no backscattering, wherein electrons are lost when they collide with an obstruction.
In electronics, backscattering hinders efficiency and generates heat.
Weyl electrons simply move through and around roadblocks, Hasan said. “It’s like they have their own GPS and steer themselves without scattering,” Hasan said. “They will move and move only in one direction since they are either right-handed or left-handed and never come to an end because they just tunnel through. These are very fast electrons that behave like unidirectional light beams and can be used for new types of quantum computing.”
Prior to the Science paper, Hasan and his co-authors published a report in the journal Nature Communications in June that theorized that Weyl fermions could exist in a tantalum arsenide crystal. Guided by that paper, the researchers used the Princeton Institute for the Science and Technology of Materials (PRISM) and Laboratory for Topological Quantum Matter and Spectroscopy in Princeton’s Jadwin Hall to research and simulate dozens of crystal structures before seizing upon the asymmetrical tantalum arsenide crystal, which has a differently shaped top and bottom.
The crystals were then loaded into a two-story device known as a scanning tunneling spectromicroscope that is cooled to near absolute zero and suspended from the ceiling to prevent even atom-sized vibrations.
An international team, led by a Bangladeshi scientist of Princeton University, has discovered an elusive massless particle theorised 85 years ago.
The particle could give a rise to faster and more efficient electronics because of its unusual ability to behave as matter and antimatter inside a crystal, according to new research.
The researchers report in the journal Science July 16 the first observation of Weyl fermions, which, if applied to next-generation electronics, could allow for a nearly free and efficient flow of electricity in electronics, and thus greater power, especially for computers, the researchers suggest.
Proposed by the mathematician and physicist Hermann Weyl in 1929, Weyl fermions have been long sought by scientists because they have been regarded as possible building blocks of other subatomic particles, and are even more basic than the ubiquitous, negative-charge carrying electron (when electrons are moving inside a crystal).
Their basic nature means that Weyl fermions could provide a much more stable and efficient transport of particles than electrons, which are the principle particle behind modern electronics.
Unlike electrons, Weyl fermions are massless and possess a high degree of mobility; the particle’s spin is both in the same direction as its motion – which is known as being right-handed – and in the opposite direction in which it moves, or left-handed.
“The physics of the Weyl fermion are so strange, there could be many things that arise from this
particle that we’re just not capable of imagining now,” said corresponding author M. Zahid Hasan, a Princeton professor of physics who led the research team.
The team included numerous researchers from Princeton’s Department of Physics, including (from left to right) graduate students Ilya Belopolski and Daniel Sanchez; Guang Bian, a postdoctoral research associate; corresponding author M Zahid Hasan, a Princeton professor of physics who led the research team; and associate research scholar Hao Zheng.
The researchers’ find differs from the other particle discoveries in that the Weyl fermion can be reproduced and potentially applied, Hasan said.
Typically, particles such as the famous Higgs boson are detected in the fleeting aftermath of particle collisions, he said.
The Weyl fermion, however, was discovered inside a synthetic metallic crystal called tantalum arsenide that the Princeton researchers designed in collaboration with researchers at the Collaborative Innovation Center of Quantum Matter in Beijing and at National Taiwan University.
The Weyl fermion possesses two characteristics that could make its discovery a boon for future electronics, including the development of the highly prized field of efficient quantum computing, Hasan explained.
For a physicist, the Weyl fermions are most notable for behaving like a composite of monopole- and antimonopole-like particles when inside a crystal, Hasan said.
This means that Weyl particles that have opposite magnetic-like charges can nonetheless move independently of one another with a high degree of mobility.
The researchers also found that Weyl fermions can be used to create massless electrons that move very quickly with no backscattering, wherein electrons are lost when they collide with an obstruction.
In electronics, backscattering hinders efficiency and generates heat.
Weyl electrons simply move through and around roadblocks, Hasan said. “It’s like they have their own GPS and steer themselves without scattering,” Hasan said. “They will move and move only in one direction since they are either right-handed or left-handed and never come to an end because they just tunnel through. These are very fast electrons that behave like unidirectional light beams and can be used for new types of quantum computing.”
Prior to the Science paper, Hasan and his co-authors published a report in the journal Nature Communications in June that theorized that Weyl fermions could exist in a tantalum arsenide crystal. Guided by that paper, the researchers used the Princeton Institute for the Science and Technology of Materials (PRISM) and Laboratory for Topological Quantum Matter and Spectroscopy in Princeton’s Jadwin Hall to research and simulate dozens of crystal structures before seizing upon the asymmetrical tantalum arsenide crystal, which has a differently shaped top and bottom.
The crystals were then loaded into a two-story device known as a scanning tunneling spectromicroscope that is cooled to near absolute zero and suspended from the ceiling to prevent even atom-sized vibrations.
