The hybridization of 2D materials and colloidal quantum dots (CQDs) has been demonstrated to be an ideal platform for infrared photodetectors due to the high mobility of 2D materials and the excellent light harvesting capability of CQDs. However, the realization of ambipolar, broadband, and room-temperature graphene–quantum dot phototransistors with complementary metal–oxide–semiconductor (CMOS) compatibility remains challenging. Here N, S codecorated graphene is deposited with PbS CQDs to fabricate a hybrid phototransistor on a silicon dioxide/silicon gate. The resulting device demonstrates a gate-tuneable ambipolar feature with a low gate bias of less than 3.3 V at room temperature in ambient. Broadband spectra from visible to near-infrared and to short wave infrared (SWIR) light can be detected with gain value of up to 10 5 and a fast response of 3 ms. Upon illumination by SWIR light at 1550 nm, the phototransistor exhibits an ultrahigh responsivity that is on the order of 10 4 AW −1 and a specific detectivity that is on the order of 10 12 Jones with a low driving voltage of 1 V. This decorated hybrid architecture illustrates the potential of graphene and CQDs to be integrated with silicon integrated circuits and opens a new path toward ambipolar photodetector fabrication.
In this work, gigahertz solidly mounted resonators (SMRs) (2.5 GHz) were designed and fabricated to construct a novel particle-resonator system to achieve the biomolecular stiffness sensing in real time. The positive frequency shift of the system was used to estimate the stiffness of biomolecules connecting between the SMR and attached particles. The working principle was revealed by the mathematical analysis of the general block-spring model of the system. Further interpretations about the mechanism of such elastic interaction from the perspective of acoustic resonant modes of SMRs were given by finite element method. Biotin-streptavidin, antibody and antigen binding system were used as model molecular linkers to study the frequency shift varied with different particle diameters and particle densities. Different linker stiffness was realized by adjusting the concentrations of antigens connected with particles which form specific binding with antibodies immobilized on the SMR. The results fairly agree with the simulation results demonstrating the proposed particle-resonator system as an effective method to realize the real-time biomolecular stiffness detection.
危险品化学品经营许可证（带存储）