With the demand for fast response of magnetic field measurement and the development of laser diode technology, self-oscillating laser-pumped atomic magnetometers have become a new development trend. In this work, we designed a portable self-oscillating VCSEL-pumped Cs atom magnetometer, including the probe (optical path) and circuits. The signal amplification and feedback loop of the magnetometer, VCSEL laser control unit, and atomic cell temperature control unit were realized. We tested the performance of the magnetometer in the metering station. Finally, The performance of the VCSEL-pumped magnetometer designed in this work was compared with that of a CS-3 lamp-pumped self-oscillating atomic magnetometer; their performance was found to be mostly in the same order of magnitude, while the power consumption of our magnetometer was 3 W less than that of the CS-3. This work represents an exploratory attempt to integrate and miniaturize a portable self-oscillating VCSEL-pumped Cs atomic magnetometer.

Periodically modulated systems with parity symmetry have been extensively investigated in recent years and exhibited various novel phenomena and potential applications in quantum technologies. In this study, a pump‐probe structure is used to observe the influence of generalized parity on the alignment spectra of magnetic resonance in a periodically biharmonic modulated warm atomic cesium ensemble. The alignment spectra are symmetric when the generalized parity of modulated Floquet atomic ensemble is present. The breaking of spectral symmetry is accompanied by the absence of generalized parity. The influence of generalized parity on atomic alignment polarization distribution is analyzed based on the perspective of the angular‐momentum probability surface. A necessary and sufficient condition for generalized parity to maintain spectral symmetry is verified experimentally and theoretically, providing a new perspective to investigative complex periodic modulation system. The results are universally applicable to atomic and solid‐state systems.

Quantum systems with multiharmonic dressing have been extensively investigated and exhibited various novel phenomena and technologies by virtue of their robust electromagnetic response. Here we mainly investigate the self-generated longitudinal Floquet modulation phenomenon of an alignment-based magnetic-resonance system with pump-probe structure dressed by two different transverse radio-frequency (rf) fields in a warm atomic cesium ensemble, both theoretically and experimentally. The self-generated Floquet modulation includes first and second harmonics, which are contributed to by linear and nonlinear processes from the weak-dressed field, respectively. The self-generated Floquet modulation dresses the alignment absorption spectra into two continua. The asymmetry of each dressed continuum is due to the generalized parity symmetry of the system being broken by the second harmonic modulation. Moreover, the nonlinear modification effect of the weak rf field on the probe verifies the existence of the four-wave mixing process in the rf band. The analytical expression, establishment process, and asymmetry analysis of the continua are given concisely. Our results can be applied to the fields of precision magnetic-field measurement, quantum control, quantum simulation, and so on. In addition, because the physical mechanism is universal, it can be applied not only to an atomic ensemble, but also to solid-state devices.

Reliability testing for Single Event Effects (SEEs) requires accurate localization of heavy-ion tracks from projection images. Conventional localization often relies on handcrafted features and geometric fitting, which is sensitive to noise and difficult to accelerate in hardware. This paper presents a lightweight detector based on YOLOv5n that treats charge tracks in Topmetal pixel sensor projections as distinct objects and directly regresses the track angle and intercept, along with bounding boxes, in a single forward pass. On a synthetic dataset, the model achieves a precision of 0.9626 and a recall of 0.9493, with line-parameter errors of 0.3930° in angle and 0.4842 pixels in intercept. On experimental krypton beam data, the detector reaches a precision of 0.92 and a recall of 0.96, with a position resolution of 52.05 μm. We further deploy the model on an Xilinx Alveo U200, achieving an average per-frame accelerator latency of 3.1 ms while preserving measurement quality. This approach enables accurate, online track localization for SEE monitoring on Field-Programmable Gate Array (FPGA) platforms.

Self-oscillating magnetometers with high sensitivity are widely used in fields such as biomedicine and remote sensing. However, few studies comprehensively consider the effect of different parameters on their performance. We examined the effects of laser intensity, resonance detuning, radio frequency magnetic field, and atomic cell on the performance of portable self-oscillating magnetometers. To obtain the atomic absorption spectrum, we solved the system’s master equation in the multipole moment form. In theory, we analyse the influencing factors on the atomic magnetic resonance (AMR) signal. In the experiment, we artificially varied the relevant parameters to control the trends of changes in the atomic absorption spectra and evaluated their performance. The results are beneficial for optimizing the parameters of portable self-oscillating magnetometers with a laser pump-probe structure.