5 results about "Eigen frequency" patented technology

The application discloses a pump-probe method for measuring and regulating the dynamic behavior of a magneto-mechanical system, and belongs to the pump-probe technical field. A specific frequency sinusoidal magnetic field is used to pump a magnetostrictive resonator, and a variable frequency magnetic field weaker than the pumping magnetic field is used for detection. The magnetostrictive resonator comprises a rectangular resonator and a double circular resonator. For the rectangular resonator with multiple eigenfrequencies, the pumping magnetic field is applied on the low-order mechanical mode to regulate the stiffness of the resonator, and then the high-order eigenmechanical mode is tuned. For the double circular resonator with two coupled mechanical modes, the pumping magnetic field with a frequency equal to the frequency difference between the two coupled mechanical modes induces AT splitting. The application lays a foundation for precise regulation in the magneto-mechanical system. The application has the advantages of high precision, remote operation, simple structure, fast test speed, low cost and the like, and can be widely used for measuring the linear and nonlinear dynamic behavior of the magneto-mechanical system.

The application discloses a kind of low-frequency noise detection methods of optically pumped laser, it is successively including multi-link synchronous acquisition and working condition insertion preparation, subzone association determination and three reference contribution solution, eigen noise reconstruction and robustness constraint, unified spectrum output and parameter backwrite closed loop, it is related to laser noise detection technical field, by simultaneously obtaining main test signal, pump reference signal, environmental reference signal and background reference signal, and according to frequency band determination reference participation condition, respectively pump contribution, environmental contribution and background contribution are calculated, eigen low-frequency intensity noise spectrum and eigen frequency noise spectrum are reconstructed, then unified result is output in combination with residual check, freeze back and splicing constraint.The method can improve low-frequency noise source distinguishing ability, result continuity and working condition adaptability.

This invention proposes a highly sensitive electromagnetic sensing device and method based on the singularity effect, belonging to the field of electromagnetic sensing technology. It includes: a first resonant unit, which is a lossy resonator; a second resonant unit, which is a resonator with added gain; and a coupling unit, which is a coupling capacitor placed between the first and second resonant units, forming a non-Hermitian coupled system. The system operates in a second-order singularity state under preset parameter conditions. When the measured medium is applied to the coupling unit, the equivalent coupling capacitance of the coupling unit changes, causing the singularity condition of the system to be disrupted, resulting in frequency splitting of the system's intrinsic frequencies. By detecting the frequency splitting characteristics, the change in the dielectric parameters of the measured medium is sensed. This invention significantly improves sensing sensitivity and resolution, and is suitable for applications such as biological detection, chemical analysis, and environmental monitoring in the microwave, millimeter-wave, and terahertz frequency bands.

The application provides a mechanical loss measuring device, and relates to the technical field of material mechanics. The mechanical loss measuring device comprises a containing assembly, which forms a vacuum chamber; a clamping assembly, which is installed in the vacuum chamber and is used for clamping a first part of a test substrate, a second part of the test substrate extends from the clamping assembly, and the second part is formed with an optical film to be measured; and a driving assembly, which is suitable for driving the second part to vibrate. The natural frequency of the clamping assembly is greater than the natural frequency of the test substrate, so that resonance coupling between the clamping assembly and the test substrate is avoided. First incident laser passes through a light transmission part and is incident on the optical film to be measured. First reflected laser, which is obtained after the first incident laser is reflected by the optical film to be measured, carries vibration information of the optical film to be measured, and the first reflected laser is used for determining the mechanical loss of the optical film to be measured. The mechanical loss measuring device can stably excite the natural vibration of the test substrate at a low frequency of 100 Hz or below, and the measurement result of the mechanical loss has accuracy.