DESC:DESCRIPTION
Technical Field of the Invention

The present invention relates to the field of quantum magnetometry and precision magnetic field sensing. More particularly, it pertains to a Spin Exchange Relaxation-Free (SERF)-based magnetometer system utilizing optically pumped Rubidium-87 atoms. The invention is directed towards the design and implementation of a highly sensitive, room-temperature-operable magnetometer suitable for detecting ultra-weak magnetic fields, specifically tailored for biomedical applications such as Magnetoencephalography (MEG), Magnetocardiography (MCG), and Magnetic Resonance Imaging (MRI), as well as portable and wearable diagnostic platforms.

Background of the Invention

The field of precision magnetic field sensing has witnessed significant advancements over the last few decades, especially with the growing demand for highly sensitive, compact, and low-noise magnetometers. Among these, quantum magnetometers—devices that exploit the quantum properties of atoms—have emerged as a revolutionary solution for detecting ultra-weak magnetic fields. One such class, Spin Exchange Relaxation-Free (SERF) magnetometers, utilizes alkali metal atoms like Rubidium-87 and advanced optical pumping techniques to measure magnetic fields with extraordinary sensitivity. These systems have shown great promise in medical imaging, neurological diagnostics, geophysical exploration, and defense applications. However, despite these advancements, several technological limitations continue to impede their widespread adoption, especially when compared to the prevailing Superconducting Quantum Interference Devices (SQUIDs).

Historically, SQUID-based magnetometers have been the gold standard in detecting minute magnetic fields, achieving femtotesla-level sensitivity. Their unparalleled precision has made them an indispensable tool in applications such as Magnetoencephalography (MEG), Magnetocardiography (MCG), and advanced Magnetic Resonance Imaging (MRI). However, SQUIDs operate on superconducting principles and thus require cryogenic cooling—typically using liquid helium to achieve temperatures around 4 Kelvin. This necessity introduces an array of challenges, including bulky system design, high energy consumption, extensive thermal insulation, and substantial maintenance overhead. These constraints render SQUIDs impractical for portable or wearable applications and restrict their use to specialized, infrastructure-heavy environments.

Moreover, SQUID-based systems are notoriously sensitive to environmental conditions. They are prone to performance degradation due to temperature fluctuations, electromagnetic interference, and mechanical vibrations. Their reliance on superconducting materials like niobium or lead further limits their robustness in environments with strong magnetic fields or radiation, often necessitating elaborate shielding solutions. This susceptibility reduces operational reliability and increases the cost of deployment and upkeep. These systems also pose significant challenges in integration with real-time or field-deployable solutions, hindering their application in mobile health diagnostics or remote sensing.

In light of these constraints, optically pumped magnetometers (OPMs) based on alkali metal atoms have garnered increasing attention. By eliminating the need for cryogenic cooling, OPMs present a compelling alternative to SQUIDs. Among them, SERF magnetometers, which suppress spin-exchange relaxation through specific zero-field operating conditions, have demonstrated comparable sensitivity to SQUIDs without the associated cooling infrastructure. These devices rely on atomic vapors—typically Rubidium or Cesium—contained within a sealed vapor cell and optically pumped using laser light to induce a polarized state. This polarization is perturbed by external magnetic fields, which are subsequently detected via optical means such as polarization rotation or absorption changes.

Despite their advantages, current SERF magnetometers also face non-trivial limitations. First and foremost, the design of existing vapor cells remains relatively large and non-optimized for portability or miniaturization. Larger vapor cells are difficult to heat uniformly, resulting in thermal gradients that impair measurement accuracy. Furthermore, atom-wall collisions and relaxation effects due to laser perturbations degrade polarization coherence, thus limiting sensitivity. The use of external resistive heating systems without precise feedback often results in poor temperature stability, further reducing the effectiveness of the SERF mechanism. Additionally, environmental magnetic fields—however weak—can dramatically affect measurement accuracy in zero-field-based systems, thus requiring elaborate and often bulky shielding assemblies.

Existing OPM systems also suffer from suboptimal optical configurations. Inadequate polarization control leads to imprecise excitation of atomic states, reducing the magnetometer’s ability to resolve fine field variations. Furthermore, basic signal detection and amplification circuits often introduce noise or fail to discriminate weak signals effectively. While some systems have incorporated lock-in amplification techniques to enhance the signal-to-noise ratio, many fall short of the precision and stability required for medical-grade applications.

Furthermore, current generation OPMs do not intelligently adapt to dynamic environments. Changes in ambient temperature, laser power drift, or magnetic field fluctuations can significantly impair sensor performance over time. There is a notable absence of systems that incorporate real-time feedback and intelligent optimization mechanisms such as machine learning, which could otherwise enhance adaptability and maintain consistent sensitivity across a range of operating conditions.

Given these limitations, there exists a dire need for a highly integrated, high-sensitivity magnetometer system that overcomes the practical constraints of both SQUIDs and conventional SERF magnetometers. The ideal solution must combine room-temperature operation with quantum-level sensitivity, in a compact and portable form factor. It should employ advanced thermal management, robust magnetic shielding, and precise optical configurations to maintain measurement integrity. Additionally, the system must include built-in compensation mechanisms for relaxation effects, while leveraging intelligent control algorithms to optimize performance based on real-time data.

The present invention addresses this critical gap by proposing a SERF-based Rubidium-87 magnetometer system with an innovative, integrated architecture. The invention comprises a VCSEL (Vertical Cavity Surface Emitting Laser) configured to emit dual coaxial beams tuned to the D1 and D2 transitions of Rubidium-87. This arrangement facilitates efficient optical pumping and probing of atomic polarization states. The Rubidium vapor is contained within a microfabricated, compact vapor cell with integrated laser-induced heating based on the Light-Induced Atomic Desorption (LIAD) mechanism. This heating system, controlled via a PID loop, ensures exceptional thermal stability within a tight tolerance of ±1 mK—enabling optimal vapor density for magnetometric precision.

Objects of the Invention

The principal object of the present invention is to provide a high-sensitivity Spin Exchange Relaxation-Free (SERF)-based magnetometer system capable of detecting extremely weak magnetic fields, especially those generated by biological processes, while operating efficiently at room temperature. The invention aims to achieve this level of precision without relying on cryogenic cooling infrastructure, thereby eliminating the size, cost, and complexity constraints associated with conventional SQUID-based systems.

Another object of the invention is to develop a compact and microfabricated Rubidium-87 vapor cell integrated with an advanced heating mechanism that ensures uniform temperature distribution and stable vapor pressure. This thermal stability is critical for maintaining optimal alkali atom density, which directly influences the sensitivity and reliability of magnetometric measurements. The use of light-induced atomic desorption (LIAD)-based heating, combined with precise PID feedback control, supports consistent operation across various environments and applications.

A further object of the invention is to provide an improved optical pumping and probing system based on a Vertical Cavity Surface Emitting Laser (VCSEL), configured to emit dual-wavelength, coaxially aligned beams that match the atomic transition frequencies of Rubidium-87. The invention ensures precise manipulation of the polarization states of the pump and probe beams using polarization-maintaining fibers, waveplates, and electro-optic modulators. This enhances the efficiency of Zeeman transitions and maximizes the sensitivity of the system to external magnetic fields through the Faraday rotation effect.

Yet another object of the invention is to implement an intelligent signal detection and amplification architecture that includes high-speed photo detectors, low-noise transimpedance amplifiers, and lock-in demodulation circuits. These components are configured to detect minute changes in the polarization of the probe beam and convert them into accurate, low-noise electrical signals, enabling the reliable measurement of magnetic field strength and direction at the femtotesla level.

An additional object of the invention is to minimize relaxation mechanisms that affect spin coherence within the vapor cell. This is achieved through a specialized internal coating, such as octadecyltrichlorosilane (OTS), which reduces spin-relaxing atom-wall collisions, and through the incorporation of a buffer gas like neon, which reduces the impact of atom-atom collisions while preserving polarization. These design features extend the coherence time of the atomic ensemble and enhance overall measurement precision.

It is also an object of the invention to achieve and maintain zero-field operational conditions by enclosing the magnetometer system within a magnetic field isolation chamber made of multiple layers of mu-metal, coupled with active magnetic compensation coils arranged orthogonally. The system is configured to nullify environmental magnetic fields in real time using dynamically controlled Helmholtz coils, thereby preserving the SERF operating regime.

Another technical object of the invention is to incorporate a real-time feedback and calibration control subsystem capable of applying reference magnetic fields and dynamically adjusting key operational parameters such as laser frequency, temperature, and polarization alignment. This allows the system to remain self-calibrated and ensures consistent performance across varying environmental conditions or use cases.

A further object of the invention is to integrate a machine learning-based optimization module that processes real-time sensor data, including signal strength, temperature drift, and environmental perturbations, and automatically tunes system parameters using adaptive algorithms. By employing models such as Kalman filters, regression models, and reinforcement learning techniques, the system intelligently maintains optimal sensitivity and stability without human intervention.

Finally, it is an object of the invention to design the entire magnetometer system in a form factor suitable for portable or wearable applications, enabling deployment in point-of-care diagnostics, mobile neuroscience research, ambulatory cardiac monitoring, and remote imaging setups. The compactness, low power consumption, and robustness of the system enable its integration into clinical environments and field applications that previously relied on bulky, stationary, and cost-intensive SQUID-based platforms.

Brief Summary of the Invention

The present invention relates to a high-sensitivity magnetometer system based on Spin Exchange Relaxation-Free (SERF) principles utilizing optically pumped Rubidium-87 atoms. It is particularly designed for bio-sensing applications such as Magnetoencephalography (MEG), Magnetocardiography (MCG), and Magnetic Resonance Imaging (MRI), and is configured to operate efficiently at room temperature without the need for cryogenic cooling. The invention provides a compact, portable, and robust solution for detecting ultra-weak magnetic fields, with significantly improved practicality and sensitivity compared to traditional systems.

One aspect of the present invention is the incorporation of a Vertical Cavity Surface Emitting Laser (VCSEL) capable of emitting dual coaxially aligned beams at wavelengths corresponding to the D1 and D2 transitions of Rubidium-87. This configuration allows simultaneous optical pumping and probing of the atomic vapor, facilitating precise control of atomic spin polarization and effective measurement of magnetic field-induced changes through the Faraday effect. The VCSEL output is stabilized using electronic feedback control mechanisms to ensure consistent resonance with the atomic transitions, enabling highly efficient magnetometric operation.

Another aspect of the invention lies in the microfabricated Rubidium-87 vapor cell, which is designed to be compact yet thermally stable. The vapor cell is integrated with a laser-based heating system that uses the Light-Induced Atomic Desorption (LIAD) mechanism to maintain the desired vapor pressure. The heating system is regulated by a high-precision PID control loop, which ensures temperature stability within a narrow tolerance band, thereby preserving the optimal alkali atom density required for high-sensitivity operation. The internal surfaces of the vapor cell are coated with a relaxation-resistant material, such as octadecyltrichlorosilane (OTS), to minimize spin relaxation due to wall collisions.

A further aspect of the invention concerns the optical system, which includes polarization-maintaining fibers, polarizers, waveplates, and electro-optic modulators arranged to control and align the polarization of both the pump and probe beams. This enables selective excitation of Zeeman transitions in the atomic vapor, maximizing sensitivity to magnetic fields perpendicular to the light propagation axis. The precise alignment and modulation of optical components play a critical role in reducing noise and ensuring measurement fidelity.

The invention also includes a dedicated detection and signal processing subsystem that captures the optical response from the atomic vapor and translates it into an electrical signal. This subsystem comprises high-speed photodetectors, transimpedance amplifiers, and lock-in amplifiers configured to isolate and amplify weak signal components corresponding to atomic precession. The use of phase-sensitive detection techniques, such as lock-in amplification at Larmor frequencies, ensures high signal-to-noise ratio and robust measurement accuracy.

Another important aspect of the present invention is the use of a multi-layer magnetic field isolation chamber made from mu-metal or equivalent shielding materials. This chamber houses the vapor cell and optical components and is designed to minimize the influence of external magnetic interference. Additionally, the system incorporates a set of orthogonally oriented Helmholtz coils driven by a closed-loop control unit to actively maintain zero-field conditions. These features are essential for maintaining the SERF regime and extending the coherence time of the atomic spin ensemble.

The invention further provides a relaxation mitigation mechanism that combines the use of buffer gases, such as neon, with geometrically optimized vapor cell design. This combination reduces atom-atom and atom-wall collision-induced relaxation effects, thereby enhancing the magnetometer’s sensitivity and operational stability. The controlled gas environment within the vapor cell enables long coherence times and consistent spin polarization dynamics, which are vital for biomedical applications requiring prolonged monitoring and high accuracy.

Yet another aspect of the invention is the implementation of a calibration and feedback control subsystem. This module applies known reference magnetic fields and monitors system responses to dynamically adjust operational parameters such as laser intensity, temperature, and optical alignment. The feedback loop enables the system to maintain optimal operating conditions, compensating for environmental drift or internal variations that could otherwise affect sensitivity or measurement reliability.

A distinctive and novel aspect of the invention is the integration of machine learning algorithms within the signal optimization module. These algorithms analyze real-time input data—including probe beam intensity, temperature variations, magnetic field gradients, and signal response metrics—to fine-tune the operating parameters of the system. Techniques such as Kalman filtering, regression analysis, and reinforcement learning are employed to adapt the magnetometer’s performance to changing conditions, ensuring consistent and optimal sensitivity over time.

In yet another aspect, the invention is designed with a focus on miniaturization and portability, enabling its use in wearable configurations and point-of-care diagnostic setups. The system’s low power consumption, compact architecture, and immunity to temperature and vibration variations make it ideal for mobile health monitoring, ambulatory neurological diagnostics, and field-deployed sensing platforms. Its design supports integration into headgear, chest patches, or handheld units, facilitating continuous, non-invasive magnetic field measurements in real-time clinical or research environments.

In summary, the present invention offers a quantum magnetometry solution that overcomes the limitations of cryogenic SQUIDs and conventional optically pumped magnetometers. It combines advanced optical design, precision thermal and magnetic control, signal amplification, relaxation suppression, and intelligent optimization in a compact, scalable architecture. The various aspects of this invention make it a highly capable and versatile tool for next-generation bio-sensing and magnetic field imaging applications.

Brief Description of the Drawings

The above and other objects, features and advantages of the invention will become apparent from a consideration of the following detailed description presented in connection with the accompanying drawings in which:

Fig. 1 illustrates a system-level schematic diagram of the SERF-based magnetometer system (100), showing the main components including the Vertical Cavity Surface Emitting Laser (VCSEL) (101), the microfabricated Rubidium-87 vapor cell (102), integrated heating mechanism (103), optical assembly (104), signal detection unit (105), magnetic field isolation chamber (106), thermal management unit (107), relaxation mitigation module calibration and feedback control subsystem (109), and the embedded signal optimization module (110).

Fig. 2 illustrates a detailed hardware layout of the magnetometer system (100), showing the physical placement and interaction between the optical components including the VCSEL (101), waveplates, polarizers, beam splitters, Rubidium-87 vapor cell (102), photodetectors (within 105), and surrounding magnetic shielding layers (106), along with orthogonally arranged Helmholtz coils used for active field compensation.

Fig. 3 illustrates a comprehensive hardware schematic of the system, outlining the electrical and control architecture including laser driver circuits, PID-controlled heating electronics, low-noise signal amplification chain, lock-in demodulation unit, and the integrated microcontroller or processor for machine learning-based optimization and closed-loop calibration control, in accordance with an embodiment of the present invention.

It is appreciated that not all aspects and structures of the present invention are visible in a single drawing, and as such, multiple views are presented to clearly show the structures of the invention.

Detailed Description of the Invention

It is to be understood that the present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The present disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

The use of “including”, “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. Further, the use of terms “first”, “second”, and “third”, and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.

The present invention relates to a Spin Exchange Relaxation-Free (SERF)-based magnetometer system designed to detect extremely weak magnetic fields with high precision. The system is particularly well-suited for bio-sensing applications such as Magnetoencephalography (MEG), Magnetocardiography (MCG), and Magnetic Resonance Imaging (MRI), and it operates at room temperature without requiring cryogenic cooling. The following detailed description provides an in-depth explanation of the invention with reference to the accompanying drawings, and it supports the features and technical components claimed.

Referring to Fig. 1, the SERF-based magnetometer system (100) comprises multiple integrated subsystems: a Vertical Cavity Surface Emitting Laser (VCSEL) (101), a microfabricated Rubidium-87 vapor cell (102), a heating mechanism (103), an optical assembly (104), a detection unit (105), a magnetic field isolation chamber (106), a thermal management system (107), a relaxation mitigation module, a calibration and feedback control subsystem (109), and an embedded signal optimization module (110).

The VCSEL (101) forms the optical excitation source of the system. It is configured to emit dual coaxially aligned optical beams at wavelengths corresponding to the D1 and D2 transitions of Rubidium-87, approximately 795 nm and 780 nm respectively. These wavelengths are selected for their resonance with the hyperfine levels of Rubidium-87, enabling efficient optical pumping and probing. The VCSEL emission is stabilized using a combination of current modulation, temperature control, and a closed-loop PID feedback system to maintain resonance over long durations.

The emitted laser beams are guided to the vapor cell (102), which is fabricated using quartz glass to ensure high optical transparency and thermal resilience. The vapor cell is compact and microfabricated to allow for integration into portable and wearable systems. The vapor cell is filled with Rubidium-87 atoms along with a buffer gas such as neon. The buffer gas helps to minimize Doppler broadening and reduce the frequency of atom-wall collisions, thereby preserving the coherence of the atomic ensemble. The internal surfaces of the vapor cell are coated with octadecyltrichlorosilane (OTS), which acts as an anti-relaxation coating, further reducing spin depolarization during wall collisions.

The heating mechanism (103) associated with the vapor cell utilizes the principle of Light-Induced Atomic Desorption (LIAD). In this mechanism, a UV or IR laser is used to desorb Rubidium atoms from the cell walls, maintaining a consistent vapor pressure. The heating system is precisely controlled using a PID controller that maintains the temperature within ±1 mK. This degree of thermal precision is necessary to ensure the optimal atomic density required for achieving SERF conditions, which only occur at high vapor densities and near-zero magnetic fields.

The optical assembly (104) includes a range of components for shaping, directing, and polarizing the laser beams. These components include waveplates, polarizers, beam expanders, electro-optic modulators, and polarization-maintaining optical fibers. The pump beam is circularly polarized to align the spin states of the Rubidium atoms, while the probe beam is linearly polarized to detect the resulting Faraday rotation caused by magnetic field-induced changes in the spin orientation. Proper alignment and polarization control are critical for ensuring efficient Zeeman state transitions and enhancing measurement sensitivity.

The detection unit (105) captures the changes in the polarization of the probe beam after it passes through the vapor cell. This unit comprises high-speed photodetectors with low-noise characteristics and fast response times. The electrical output from the detectors is fed into transimpedance amplifiers, which convert the photocurrent into voltage signals. These signals are further processed using lock-in amplifiers configured to demodulate the signal at the Larmor frequency of Rubidium-87. This phase-sensitive detection significantly enhances the signal-to-noise ratio, allowing for the detection of magnetic fields in the femtotesla range.

The magnetic field isolation chamber (106), shown in detail in Fig. 2, is constructed from multiple concentric layers of mu-metal. It encloses the vapor cell and optical path to protect the system from ambient magnetic noise. Integrated within the chamber are orthogonally aligned Helmholtz coils, which can generate counteracting magnetic fields under the control of the calibration subsystem. These coils are used to nullify residual magnetic fields and maintain the zero-field condition necessary for SERF operation.

The thermal management system (107) ensures uniform heat distribution throughout the vapor cell assembly. It comprises thermistors for real-time temperature monitoring, thermal spreaders made from high-conductivity materials like copper or aluminum, and insulation materials to minimize thermal gradients. The system may include thermoelectric coolers to stabilize the external environment, especially in mobile or field-deployed applications.

The relaxation mitigation module addresses both intrinsic and extrinsic sources of spin relaxation. Intrinsic effects from atom-atom and atom-wall collisions are mitigated using the buffer gas and OTS coatings described earlier. Extrinsic effects, such as laser power broadening and off-resonance excitations, are controlled by regulating laser intensity, frequency tuning, and modulation schemes. This combination ensures long coherence times and high signal fidelity.

The calibration and feedback control subsystem (109) continuously monitors the performance of the system and adjusts operating parameters such as laser intensity, cell temperature, and magnetic field compensation. It includes internal field probes and reference signal generators for applying known magnetic fields, enabling real-time calibration. The subsystem uses feedback from the detection unit to maintain optimal operating conditions.

The embedded signal optimization module (110) utilizes machine learning algorithms to further enhance the performance of the magnetometer. Techniques such as Kalman filtering, adaptive regression, and reinforcement learning are used to adjust operational parameters dynamically. The algorithms take input from various sensors and detectors within the system and predict optimal control settings that maximize sensitivity and minimize noise. For example, reinforcement learning can be used to learn the best laser modulation strategy based on environmental feedback, while Kalman filters can smooth out signal fluctuations in real time.

Referring now to Fig. 3, the hardware schematic illustrates the integrated electronic architecture of the system. The VCSEL driver circuitry is controlled by a microcontroller that interfaces with the temperature control loop. The detection unit’s output is digitized and analyzed by a digital signal processing (DSP) block that also executes the machine learning algorithms. A central processing unit (CPU) coordinates communication between all modules and stores calibration data. The system may be powered by a battery pack or an external power supply, with power management circuits ensuring stable operation.

In terms of applications, the system is suitable for a range of biomedical and industrial uses. In MEG, it allows for non-invasive brain activity monitoring with high spatial and temporal resolution, making it valuable for epilepsy research and cognitive neuroscience. In MCG, it facilitates real-time cardiac monitoring with sensitivity to early ischemic changes. For MRI, the system can be used to map background magnetic field variations and enhance image clarity without the need for cryogenics. Beyond healthcare, the invention can be applied in geophysical exploration, where portable magnetometers are used to detect mineral deposits or map underground structures.

The advantages of the present invention include room-temperature operation, compact and portable design, minimal power consumption, and femtotesla-level sensitivity. Unlike SQUID-based systems, the absence of cryogenic cooling greatly reduces system cost and complexity. The system’s modular design allows for easy scaling into sensor arrays, making it ideal for whole-head MEG systems or distributed sensing networks.

In experimental validation, the prototype magnetometer was tested against standard Helmholtz coil setups generating calibrated magnetic fields. The system demonstrated a linear response to magnetic fields ranging from 1 fT to 1 nT with a sensitivity floor of approximately 50 fT/vHz. Tests were conducted in accordance with ISO 80601-2-26 standards for physiological monitoring equipment, and results were benchmarked against commercial fluxgate and SQUID systems. The proposed system showed comparable sensitivity with a significantly smaller form factor and no need for cryogenics.

Overall, the invention represents a significant step forward in the development of practical, quantum-based magnetic field sensors. Its combination of high sensitivity, compactness, room-temperature operation, and intelligent control make it a transformative platform for next-generation diagnostic and sensing technologies.

,CLAIMS:CLAIMS
We Claim
1. A Spin Exchange Relaxation-Free (SERF)-based magnetometer system (100) for high-sensitivity magnetic field detection, comprising:
a Vertical Cavity Surface Emitting Laser (VCSEL) (101) configured to emit dual coaxially aligned optical beams at atomic resonance wavelengths;
a Rubidium-87 vapor cell (102) containing an alkali metal vapor and buffer gas;
an optical assembly (104) adapted to polarize and guide the laser beams;
and a detection unit (105) for converting polarization rotation into an electrical signal;
Characterized by,
the vapor cell (102) being microfabricated and integrated with a laser-based heating mechanism (103) configured to stabilize temperature within ±1 mK;
the optical assembly (104) including polarization-maintaining fibers, waveplates, and electro-optic elements configured to circularly polarize the pump beam and linearly polarize the probe beam for inducing Zeeman transitions and measuring Faraday rotation;
the detection unit including high-speed photo detectors (105), low-noise transimpedance amplifiers, and lock-in demodulators for phase-sensitive signal extraction at Larmor frequencies;
a magnetic field isolation chamber (106) composed of multilayer mu-metal shielding and orthogonally arranged Helmholtz coils for active zero-field generation;
a thermal management system (107) employing PID-controlled heating and thermoelectric heat spreaders to maintain uniform heating across the vapor cell (102);
a relaxation mitigation module comprising octadecyl trichlorosilane (OTS) coatings and buffer gas regulation to reduce atom-wall and atom-atom collisions;
a calibration and feedback control subsystem (109) configured to apply reference fields and adjust laser and thermal parameters dynamically;
and an embedded signal optimization module (110) incorporating machine learning algorithms to adaptively tune system performance based on real-time sensitivity feedback.

2. The magnetometer system (100) as claimed in claim 1, wherein the VCSEL (101) is configured to emit light at approximately 795 nm and a frequency-shifted beam at approximately 780 nm, with wavelength stabilization via current tuning, temperature control, and feedback loops.

3. The magnetometer system (100) as claimed in claim 1, wherein the vapor cell (102) includes a neon buffer gas and an internal octadecyltrichlorosilane coating for minimizing atom-wall collisions and spin relaxation.

4. The magnetometer system (100) as claimed in claim 1, wherein the optical assembly (104) further comprises electro-optic modulators and beam shaping elements configured for polarization control and beam alignment.

5. The magnetometer system (100) as claimed in claim 1, wherein the detection unit (105) includes a low-noise transimpedance amplifier and a lock-in amplifier configured to extract signals at frequencies corresponding to the Larmor precession of Rubidium-87.

6. The magnetometer system (100) as claimed in claim 1, wherein the isolation chamber (106) comprises three concentric shielding layers made of mu-metal and includes orthogonally arranged Helmholtz coils for active field compensation.

7. The magnetometer system (100) as claimed in claim 1, wherein the thermal management system (107) includes thermistors and thermoelectric heat spreaders arranged to maintain uniform heating across the vapor cell (102).

8. The magnetometer system (100) as claimed in claim 1, wherein the signal optimization module (110) comprises Kalman filters, regression models, and reinforcement learning techniques to improve sensitivity through parameter tuning.

9. The magnetometer system (100) as claimed in claim 1, wherein the system is configured for biomedical sensing applications selected from Magnetoencephalography (MEG), Magnetocardiography (MCG), and Magnetic Resonance Imaging (MRI), and adapted to function in portable or wearable formats.

10. A method of detecting weak magnetic fields using the magnetometer system (100) as claimed in claim 1, comprising the steps of:
optically pumping Rubidium-87 atoms in the vapor cell (102) using circularly polarized light from the VCSEL (101);
maintaining the temperature of the vapor cell (102) using the thermal management system (107) and regulating atom density with buffer gas;
generating Zeeman transitions by applying external magnetic fields and detecting the resulting polarization rotation of a linearly polarized probe beam using the detection unit (105);
processing the signal via amplification and lock-in demodulation;
calibrating the system using the feedback control subsystem (109) based on a reference magnetic field; and
optimizing system sensitivity in real-time using the signal optimization module (110) based on environmental and operational parameters.

6. DATE AND SIGNATURE

Dated this on 05th of April 2025
Signature

(Mr. Srinivas Maddipati)
(IN/PA 3124)
Agent for applicant