The structure and distribution of nitrogen-vacancy(NV)centers in diamond are critical for their performance in quantum technologies,such as quan-tum computing and sensing.For quantum sensing applications,achieving a h...The structure and distribution of nitrogen-vacancy(NV)centers in diamond are critical for their performance in quantum technologies,such as quan-tum computing and sensing.For quantum sensing applications,achieving a high density of NV centers is essential,and both the structural arrange-ment of the ensemble NV centers and their distribution significantly influ-ence sensitivity.However,existing techniques lack the resolution required to accurately characterize the atomic-scale structure,distribution,and strain field of NV centers.In this study,we present the first atomic-scale im-aging of ensemble NV center structures using multislice electron ptychog-raphy(MEP)in a diamond containing 27 ppm NV centers.Our direct imag-ing reveals that the ensemble NV centers can be characterized as clusters of individual NV centers,rather than being tightly segregated or randomly distributed at atomic scale.Each NV cluster comprises more than four sin-gle NV centers aligned along three or more atomic columns within a depth range of 1–5 nm along[110]projected direction,with the spacing between clusters of approximately 1–2 nm along the(110)projection plane.This work provides valuable insights into the true structural characteristics of dense NV centers,offering guidance for understanding the structure-prop-erty correlations that influence their performance in quantum sensing and related applications.展开更多
Untethered and self-transformable miniature robots are capable of performing reconfigurable deformation and on-demand locomotion,which aid the traversal toward various lumens,and bring revolutionary changes for target...Untethered and self-transformable miniature robots are capable of performing reconfigurable deformation and on-demand locomotion,which aid the traversal toward various lumens,and bring revolutionary changes for targeted delivery in gastrointestinal(GI)tract.However,the viscous non-Newtonian liquid environment and plicae gastricae obstacles severely hamper high-precision actuation and payload delivery.Here,we developed a low-friction soft robot by assembly of densely arranged cone structures and grafting of hydrophobic monolayers.The magnetic orientation encoded robot can move in multiple modes,with a substantially reduced drag,terrain adaptability,and improved motion velocity across the non-Newtonian liquids.Notably,the robot stiffness can be reversibly controlled with magnetically induced hardening,enabling on-site scratching and destruction of antibiotic-ineradicable polymeric matrix in biofilms with a low-frequency magnetic field.Furthermore,the magnetocaloric effect can be utilized to eradicate the bacteria by magnetocaloric effect under high-frequency alternating field.To verify the potential applications inside the body,the clinical imaging-guided actuation platforms were developed for vision-based control and delivery of the robots.The developed low-friction robots and clinical imaging-guided actuation platforms show their high potential to perform bacterial infection therapy in various lumens inside the body.展开更多
基金supported by National Natural Science Foundation of China(grant nos.52250402,52025025,12374012,52325102)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(grant no.20241310006)+4 种基金Science Fund for Distinguished Young Scholars of Zhejiang Province(LR22E020003)National Key R&D Program of China(grant no.2022YFB2404400)Shan-dong Provincial Natural Science Foundation(ZR2023JQ001)the China Postdoctoral Sci-ence Foundation funded project(2024M761653)financial assistance from the Shuimu Tsinghua Scholar Program.
文摘The structure and distribution of nitrogen-vacancy(NV)centers in diamond are critical for their performance in quantum technologies,such as quan-tum computing and sensing.For quantum sensing applications,achieving a high density of NV centers is essential,and both the structural arrange-ment of the ensemble NV centers and their distribution significantly influ-ence sensitivity.However,existing techniques lack the resolution required to accurately characterize the atomic-scale structure,distribution,and strain field of NV centers.In this study,we present the first atomic-scale im-aging of ensemble NV center structures using multislice electron ptychog-raphy(MEP)in a diamond containing 27 ppm NV centers.Our direct imag-ing reveals that the ensemble NV centers can be characterized as clusters of individual NV centers,rather than being tightly segregated or randomly distributed at atomic scale.Each NV cluster comprises more than four sin-gle NV centers aligned along three or more atomic columns within a depth range of 1–5 nm along[110]projected direction,with the spacing between clusters of approximately 1–2 nm along the(110)projection plane.This work provides valuable insights into the true structural characteristics of dense NV centers,offering guidance for understanding the structure-prop-erty correlations that influence their performance in quantum sensing and related applications.
基金supported by the National Natural Science Foundation of China(22102104 and U22A2064)the General Research Fund(project no.14203123)+7 种基金National Key Research and Development Project(grant no.2023YFB4705300)the Shenzhen Science and Technology Program(JCYJ20220531103409021 and JCYJ20220818101611025)the Guangdong Basic and Applied Basic Research Foundation(2021A1515010672 and 2022B1515120010)the Research Impact Fund(project no.R4015-21)Research Fellow Scheme(project no.RFS2122-4S03)the EU-Hong Kong Research and Innovation Cooperation Co-funding Mechanism(project no.E-CUHK401/20)from the Research Grants Council(RGC)of Hong Kongthe support from the SIATCUHK Joint Laboratory of Robotics and Intelligent Systems and the Multi-Scale Medical Robotics Center(MRC),InnoHK,at the Hong Kong Science ParkGuangdong University Students Science and Technology Innovation Cultivation Special Fund Project with project no.pdjh2022b0446.
文摘Untethered and self-transformable miniature robots are capable of performing reconfigurable deformation and on-demand locomotion,which aid the traversal toward various lumens,and bring revolutionary changes for targeted delivery in gastrointestinal(GI)tract.However,the viscous non-Newtonian liquid environment and plicae gastricae obstacles severely hamper high-precision actuation and payload delivery.Here,we developed a low-friction soft robot by assembly of densely arranged cone structures and grafting of hydrophobic monolayers.The magnetic orientation encoded robot can move in multiple modes,with a substantially reduced drag,terrain adaptability,and improved motion velocity across the non-Newtonian liquids.Notably,the robot stiffness can be reversibly controlled with magnetically induced hardening,enabling on-site scratching and destruction of antibiotic-ineradicable polymeric matrix in biofilms with a low-frequency magnetic field.Furthermore,the magnetocaloric effect can be utilized to eradicate the bacteria by magnetocaloric effect under high-frequency alternating field.To verify the potential applications inside the body,the clinical imaging-guided actuation platforms were developed for vision-based control and delivery of the robots.The developed low-friction robots and clinical imaging-guided actuation platforms show their high potential to perform bacterial infection therapy in various lumens inside the body.
