Quantum sensing improves Purdue quantum NMR Spectroscopy
NMR analyses
Purdue Researchers Use 2D Materials for Atomic-Scale Quantum Sensing.
A Purdue University invention may improve atomic-level nuclear magnetic resonance (NMR) spectroscopy, advancing quantum sensing. This discovery, using rare carbon-13 isotopes and 2D materials, has major implications for biological molecular research and quantum computers and communications systems.
From MRI to Atomic Resolution: Overcoming Limitations
NMR spectroscopy, which studies biological molecules in disease and therapeutic research, and MRI, which diagnoses patients, underpin this discovery. MRI and NMR employ the small magnetic fields produced by particles like hydrogen nucleus protons impacted by their surroundings. These methods flip these nuclei with radio waves, and the signals they produce when they align reveal their environment.
NMR analyses
Purdue Researchers Use 2D Materials for Atomic-Scale Quantum Sensing.
A Purdue University invention may improve atomic-level nuclear magnetic resonance (NMR) spectroscopy, advancing quantum sensing. This discovery, using rare carbon-13 isotopes and 2D materials, has major implications for biological molecular research and quantum computers and communications systems.
From MRI to Atomic Resolution: Overcoming Limitations
NMR spectroscopy, which studies biological molecules in disease and therapeutic research, and MRI, which diagnoses patients, underpin this discovery. MRI and NMR employ the small magnetic fields produced by particles like hydrogen nucleus protons impacted by their surroundings. These methods flip these nuclei with radio waves, and the signals they produce when they align reveal their environment.
Standard NMR spectroscopy, which takes milligram-sized samples and has a resolution of 100 micrometres, can study molecular structures but not individual atoms. According to Purdue professor Tongcang Li, “Conventional NMR spectroscopy is limited to measuring large samples of molecules.” This new work aims to remedy this. We want single-molecule detection and analysis technology.
2D Materials with Spin Defects: A New Method
Li's lab is pioneering this research by applying magnetic resonance to 2D materials sheets, just a few atoms thick. This unique method exploits spin defects, purposely manufactured imperfections in the 2D material, to reveal the structure of biological molecules put directly on top. The biological sample's atoms alter spin defects, modifying the magnetic resonance signal and disclosing atomic-level structural features because the molecule and 2D material are so close.
The 2D material is hexagonal boron nitride (hBN), which alternates boron and nitrogen atoms. Natural flaws result from atom absences. Previous research by Li's team used electrons in boron vacancies as quantum sensors to manage and collect data from adjacent nitrogen nuclei in 2022. Their resolution was 1 micrometre. Despite being better than typical NMR, this could not provide single-nucleus resolution for atom identification.
Carbon-13 Breakthrough
Li's team studied hBN carbon defects for resolution. They chose carbon-13, a rare isotope with an additional neutron that produces a magnetic field suitable for magnetic resonance uses, because conventional carbon lacks one.
To inject these crucial carbon-13 defects, scientists followed a precise approach. After employing 99% carbon-13-enriched carbon dioxide gas, scientists used an electric field to blast atoms at a hBN sample. This reaction displaced boron and nitrogen atoms in the hBN crystal lattice with carbon-13 and oxygen. Researchers confirmed these unusual carbon-13-containing defects using optical microscopy.
The carbon-13 nucleus was used to examine the elaborate nature of these newly generated defects in the hBN lattice. Using optically detected nuclear magnetic resonance, they received signals from the carbon-13 nucleus that revealed its surroundings. Never before has a carbon-13 nuclear spin in a two-dimensional solid been spectroscopically single-spin.
Theorist Yuan Ping from the University of Wisconsin-Madison helped the researchers identify defect structures in two of three categories.
Applications and Future of Quantum
Carbon-13's nuclear spin has a long coherence period at ambient temperature, a major discovery. This characteristic is useful for quantum computing applications that require long-term state preservation.
Li said this was the first spin defect in hexagonal boron nitride generated using carbon 13. Our research improves quantum sensing by using nuclear spins as quantum memory and comprehending hexagonal boron nitride spin defects. Quantum sensing, communications, and computation could benefit from this research.
The DOE, NSF, and Gordon and Betty Moore Foundation funded this groundbreaking work.
University of Purdue
Purdue University, one of the top ten US public universities, is known for its knowledge discovery, distribution, and application. Purdue's 14-year tuition freeze shows its commitment to affordability and accessibility.
More than 58,000 students attend the university's main campuses in West Lafayette and Indianapolis. The National Science Foundation's Industry-University Cooperative Research Centre for Quantum Technologies in Indiana is directed by Tongcang Li, a Purdue Quantum Science and Engineering Institute member. He teaches physics, astronomy, and electrical and computer engineering in the Colleges of Science and Engineering.
Li's lab is pioneering this research by applying magnetic resonance to 2D materials sheets, just a few atoms thick. This unique method exploits spin defects, purposely manufactured imperfections in the 2D material, to reveal the structure of biological molecules put directly on top. The biological sample's atoms alter spin defects, modifying the magnetic resonance signal and disclosing atomic-level structural features because the molecule and 2D material are so close.
The 2D material is hexagonal boron nitride (hBN), which alternates boron and nitrogen atoms. Natural flaws result from atom absences. Previous research by Li's team used electrons in boron vacancies as quantum sensors to manage and collect data from adjacent nitrogen nuclei in 2022. Their resolution was 1 micrometre. Despite being better than typical NMR, this could not provide single-nucleus resolution for atom identification.
Carbon-13 Breakthrough
Li's team studied hBN carbon defects for resolution. They chose carbon-13, a rare isotope with an additional neutron that produces a magnetic field suitable for magnetic resonance uses, because conventional carbon lacks one.
To inject these crucial carbon-13 defects, scientists followed a precise approach. After employing 99% carbon-13-enriched carbon dioxide gas, scientists used an electric field to blast atoms at a hBN sample. This reaction displaced boron and nitrogen atoms in the hBN crystal lattice with carbon-13 and oxygen. Researchers confirmed these unusual carbon-13-containing defects using optical microscopy.
The carbon-13 nucleus was used to examine the elaborate nature of these newly generated defects in the hBN lattice. Using optically detected nuclear magnetic resonance, they received signals from the carbon-13 nucleus that revealed its surroundings. Never before has a carbon-13 nuclear spin in a two-dimensional solid been spectroscopically single-spin.
Theorist Yuan Ping from the University of Wisconsin-Madison helped the researchers identify defect structures in two of three categories.
Applications and Future of Quantum
Carbon-13's nuclear spin has a long coherence period at ambient temperature, a major discovery. This characteristic is useful for quantum computing applications that require long-term state preservation.
Li said this was the first spin defect in hexagonal boron nitride generated using carbon 13. Our research improves quantum sensing by using nuclear spins as quantum memory and comprehending hexagonal boron nitride spin defects. Quantum sensing, communications, and computation could benefit from this research.
The DOE, NSF, and Gordon and Betty Moore Foundation funded this groundbreaking work.
University of Purdue
Purdue University, one of the top ten US public universities, is known for its knowledge discovery, distribution, and application. Purdue's 14-year tuition freeze shows its commitment to affordability and accessibility.
More than 58,000 students attend the university's main campuses in West Lafayette and Indianapolis. The National Science Foundation's Industry-University Cooperative Research Centre for Quantum Technologies in Indiana is directed by Tongcang Li, a Purdue Quantum Science and Engineering Institute member. He teaches physics, astronomy, and electrical and computer engineering in the Colleges of Science and Engineering.
