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Chengbo Zhu

Publications and source records attributed to Chengbo Zhu.

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mmWave-Diffusion:A Novel Framework for Respiration Sensing Using Observation-Anchored Conditional Diffusion Model

Millimeter-wave (mmWave) radar enables contactless respiratory sensing,yet fine-grained monitoring is often degraded by nonstationary interference from body micromotions.To achieve micromotion interference removal,we propose mmWave-Diffusion,an observation-anchored conditional diffusion framework that directly models the residual between radar phase observations and the respiratory ground truth,and initializes sampling within an observation-consistent neighborhood rather than from Gaussian noise-thereby aligning the generative process with the measurement physics and reducing inference overhead. The accompanying Radar Diffusion Transformer (RDT) is explicitly conditioned on phase observations, enforces strict one-to-one temporal alignment via patch-level dual positional encodings, and injects local physical priors through banded-mask multi-head cross-attention, enabling robust denoising and interference removal in just 20 reverse steps. Evaluated on 13.25 hours of synchronized radar-respiration data, mmWave-Diffusion achieves state-of-the-art waveform reconstruction and respiratory-rate estimation with strong generalization. Code repository:https://github.com/goodluckyongw/mmWave-Diffusion.

eess.IV

Theoretical study of transport properties of B40 and its endohedral borospherenes in single-molecule junctions

C60 fullerene has been studied extensively, as it is considered to be a good candidate for building single-molecule junctions. Here, we theoretically demonstrate that the conductance of single-molecule junctions based on a newly discovered molecule, borospherene (B40), is comparable to that for the C60-based junction with its more delocalized π electrons. The charge injection efficiency in the B40-based junction is improved, as up to 7 atoms in direct contact with the electrode are possible in the Au-B40-Au junction. Interestingly, a higher number of atoms in direct contact with the electrode does not result in a higher number of conduction channels because of the unique chemical bonding in the B40 molecule, without two-center two- electron bonds. The transport properties of Au-B40-Au junctions can be proved by doping. With a Ca, Sr, or Y atom encapsulated into the B40 cage, the conductance at zero bias increases significantly. Moreover, our calculations show that the lowest unoccupied molecular orbital dominates the low-bias transport, as the thermopower in these junctions is negative. Our study indicates that B40 is an attractive new platform for designing highly conductive single-molecule junctions for future molecular circuits.

cond-mat.mes-hall

Tuning the conductance of H$_{2}$O@C$_{60}$ by position of the encapsulated H$_{2}$O

The change of conductance of single molecule junctions in response to various external stimuli is the fundamental mechanism for single-molecule electronic devices with multiple functionalities. We propose a concept that the conductance of molecule systems can be tuned from its inside. The conductance is varied in C$_{60}$ with encapsulated H$_{2}$O, H$_{2}$O@C$_{60}$. The transport properties of the H$_{2}$O@C$_{60}$-based nanostructure sandwiched between electrodes are studied using first-principles calculations based on the non-equilibrium Green's function formalism. Our results show that the conductance of the H$_{2}$O@C$_{60}$ is sensitive to the position of the H$_{2}$O and its dipole direction inside the cage with changes in conductance up to 20%. Our study paves a way for the H$_{2}$O@C$_{60}$ molecule to be a new platform for novel molecule based electronics and sensors.

cond-mat.mes-hall