A5005704197- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Scientific Measurement and Uncertainty Evaluation
- Hemodynamic Monitoring and Therapy
- Advanced Fiber Laser Technologies
- RNA modifications and cancer
- Radiation Detection and Scintillator Technologies
- Radiation Effects and Dosimetry
- Cancer-related molecular mechanisms research
- Cardiovascular Syncope and Autonomic Disorders
- Advanced Radiotherapy Techniques
- BIM and Construction Integration
- Evaluation and Optimization Models
- Head and Neck Cancer Studies
- Salivary Gland Tumors Diagnosis and Treatment
- Ferroptosis and cancer prognosis
- Construction Project Management and Performance
- Protease and Inhibitor Mechanisms
University of Chinese Academy of Sciences
2020-2023
Chinese Academy of Sciences
2020-2023
Wuhan Institute of Physics and Mathematics
2020-2023
Bengbu Medical College
2022
Huazhong University of Science and Technology
2020
University of South China
2017
Ningxia Medical University
2013
Zhejiang Chint Electrics (China)
2004
We present a liquid-nitrogen-cooled $\mathrm{Ca}$${}^{+}$ optical clock with an overall systematic uncertainty of $3.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}18}$. In contrast to the room-temperature that we have reported previously, cryogenic black-body radiation (BBR) shield in vacuum is cooled $82\ifmmode\pm\else\textpm\fi{}5$ K using liquid nitrogen. also implement ion trap reduced heating rate and improved laser cooling. This allows temperature fall Doppler-cooling limit...
We present a robust, transportable ${\mathrm{Ca}}^{+}$ optical clock, with systematic uncertainty of $1.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}17}$ limited by the black-body radiation (BBR) field evaluation and an uptime rate $>75%$ over 20-day period. The clock is then installed in air-conditioned car trailer, making it more convenient for applications. Referenced to stationary laboratory geopotential measurements are made total 0.33 m (statistically 0.25 systematically 0.22...
We present the compact long-term nearly continuous operation of a room-temperature ${\mathrm{Ca}}^{+}$-optical-clock setup towards transportable clock, achieving an overall systematic uncertainty 4.8 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}18}$ and uptime rate 97.8% over 8-day period. The active liquid-cooling scheme is adopted, combined with precise temperature measurement 13 sensors both inside outside vacuum chamber to ensure accurate evaluation thermal environment for...
Progress of the 40 Ca + ion optical clock based on 4 2 S 1/2 – 3d D 5/2 electric quadrupole transition is reported. By setting drive frequency to “magic” Ω 0 , uncertainty caused by scalar Stark shift and second-order Doppler induced micromotion reduced 10 −19 level. precisely measuring differential static polarizability Δ α due blackbody radiation (BBR) (coefficient) With help a integrating servo algorithm, error −18 The total fractional then improved 2.2× −17 whereas this value mainly...
The fractional uncertainty of the 40Ca+ optical clock in our laboratory has been evaluated to be 2.2×10−17, but it is difficult evaluate statistical output frequency at this level, limited by stability associated with quantum projection noise (QPN). A reduction required shorten averaging time for a certain level. To improve stability, Ramsey method introduced locking process. reliability and continuity, we introduce idea using auxiliary Rabi probes avoid fringe slips interrogation...
Background: Molecular typing based on deoxyribonucleic acid (DNA) methylation and gene expression can extend understandings of the molecular mechanisms involved in lung adenocarcinoma (LUAD) enhance current diagnostic, treatment, prognosis prediction approaches. Methods: Gene DNA data sets LUAD were obtained from The Cancer Genome Atlas (TCGA), differential levels analyzed. Results: We successfully divided samples into 2 clinically relevant subtypes with significantly different survival...
Here we present a liquid nitrogen-cooled Ca^+ optical clock with an overall systematic uncertainty of 3*10^-18. In contrast the room-temperature that have reported previously, temperature blackbody radiation (BBR) shield in vacuum has been reduced to 82(5) K using nitrogen. An ion trap lower heating rate and improved cooling lasers were also introduced. This allows Doppler limit during operation, due ion's secular (thermal) motion is < 1*10^-18. The probe laser light shift servo error are...
The instability of the clock laser is one primary factors limiting optical clocks. We present an ultra-stable based on a 30-cm-long transportable cavity with ∼3 × 10
We constructed a transportable 40Ca+ optical clock (with an estimated minimum systematic shift uncertainty of 1.3*10^(-17) and stability 5*10^(-15)/sqrt{tau} ) that can operate outside the laboratory. transported it from Innovation Academy for Precision Measurement Science Technology, Chinese Sciences, Wuhan to National Institute Metrology, Beijing. The absolute frequency 729 nm transition was measured up 35 days by tracing its second International System Units. Some improvements were...
In this review, the improvements made in past two decades for 40Ca+ optical clocks China are presented. Uncertainty of below 1.3×10−17 was achieved by applying “magic” RF trapping frequency and introducing a generalized Ramsey excitation scheme. The stability has been improved to 2.5×10−15/τ with an uptime rate 93.8% implementing ameliorated lock algorithms A long-term clock comparison shows 6.3 × 10−18 averaging time 524 000 s. robust transportable installed air-conditioned car trailer can...
Abstract Here we present a liquid nitrogen-cooled Ca + optical clock with an overall systematic uncertainty of 3×10 -18 . In contrast the room-temperature Ca+ that have reported previously, temperature blackbody radiation (BBR) shield in vacuum has been reduced to 82(5) K using nitrogen. An ion trap lower heating rate and improved cooling lasers were also introduced. This allows Doppler limit during operation, due ion’s secular (thermal) motion is < 1×10 The probe laser light shift servo...
We constructed a transportable 40Ca+ optical clock (with an estimated minimum systematic shift uncertainty of 1.3*10^(-17) and stability 5*10^(-15)/sqrt{tau} ) that can operate outside the laboratory. transported it from Innovation Academy for Precision Measurement Science Technology, Chinese Sciences, Wuhan to National Institute Metrology, Beijing. The absolute frequency 729 nm transition was measured up 35 days by tracing its second International System Units. Some improvements were...
We present a compact, long-term nearly continuous operation of room-temperature Ca$^+$ optical clock setup towards transportable clock, achieving an overall systematic uncertainty $4.8\times 10^{-18}$ and uptime rate 97.8% over 8-day period. The active liquid-cooling scheme is adopted, combined with the precise temperature measurement 13 sensors both inside outside vacuum chamber to ensure accurate evaluation thermal environment for clock. environmental evaluated as 293.31(0.4) K,...
Objective To validate the feasibility of simulationmethod and reliability simulationresult through comparison between simulation measurement energy spectrum from medical diagnostic X-ray (RQR-Radiation qualities in radiation beams emerging source assembly). Methods A simplified model RQR quality was established using code BEAMnrc. The same were measured a plane high-purity germanium spectrometer, compared with simulationresult. Results The difference spectral distribution less...
Abstract Optical clocks are important for precise measurements in the field of physics. As reported, both instability and uncertainty optical lattice more than two orders magnitude smaller those best microwave clocks. Therefore, near future, could be used to redefine second. Nevertheless, an clock with reliability comparable has not been achieved thus far. In this paper, we compared frequencies Ca^+ that were nearly continuously operated 31 days. Through comparison experiment, frequency...