Rapid Fire
Advancements in Magnetic Field Measurements
- 11 Jul 2025
- 3 min read
Scientists at the Raman Research Institute (RRI) have developed a technique called Raman-Driven Spin Noise Spectroscopy (RDSNS) which can be incorporated into an all-optical quantum magnetometer to improve magnetic field measurements.
RDSNS (Raman-Driven Spin Noise Spectroscopy):
- About: RDSNS is an advanced all-optical technique for measuring magnetic fields using laser light and Rubidium atoms.
- Atoms naturally exhibit tiny, random spin movements, known as spin noise.
- When exposed to a magnetic field, the pattern of this noise changes.
- By detecting these changes with laser light, researchers can measure the magnetic field without disturbing the atoms.
- Key Advantages:
- It enables shield-free, compact/portable, and field-deployable magnetic sensing with a wide dynamic range and high sensitivity.
- It remains effective even in outdoor or noisy environments and is resistant to electrical and mechanical interference.
- Applications: RDSNS is useful in medical imaging (MRI alternative), geological surveys (mineral detection), space exploration (planetary magnetic fields), and quantum research (atomic and spin studies).
Magnetometer:
- About: A magnetometer is a device used to measure the strength and direction of magnetic fields, commonly applied in medical imaging, navigation, and earth/space studies.
- In ocean exploration, it helps detect shipwrecks, aircraft debris, and geological features on the seafloor.
- Working: The Earth’s magnetic field is generated by molten iron and nickel in its outer core and varies by location.
- Magnetometers detect this variation by recording magnetic readings (typically at 1 Hz). When encountering ferrous objects (like anchors, wreckage, or basalt), the device senses magnetic anomalies, sudden, unexpected changes in the field.
- Modern Magnetometers: Modern magnetometers such as Optically Pumped Atomic Magnetometers (OPAMs) and Spin-Exchange Relaxation-Free (SERF) use laser light and alkali atoms (e.g., Rubidium) to detect magnetic fields with high sensitivity.
- However, they require costly magnetic shielding, function only in noise-free lab settings, and have a limited detection range.
| Read More: Aditya-L1: Deployment of Magnetometer Boom in Sun's Orbit |
