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Spin noise explores local magnetic fields in a semiconductor
Ivan I Ryzhov1, Gleb G Kozlov1, Dmitrii S Smirnov2
1St.-Petersburg State University, Spin Optics Laboratory, Peterhof, St.-Petersburg 198504, Russia.
Scientific Reports
|February 18, 2016
Summary
Spin noise spectroscopy reveals new magnetic field insights. Researchers observed an "optical field" in n-GaAs microcavities, linked to the optical Stark effect from polarized light.
Area of Science:
- Condensed Matter Physics
- Quantum Optics
- Spectroscopy
Background:
- Spin noise spectroscopy has advanced magnetic resonance and optical spectroscopy.
- Investigating electron spin dynamics in semiconductor microcavities is crucial for quantum technologies.
Purpose of the Study:
- To demonstrate the magnetometric potential of spin noise spectroscopy.
- To study magnetic fields acting on an n-GaAs electron spin system within a high-Q microcavity.
Main Methods:
- Utilizing spin noise spectroscopy with elliptically polarized light probing.
- Analyzing spin noise spectra in an n-GaAs layer inside a high-Q microcavity.
- Applying external magnetic fields and studying optically induced fields.
Main Results:
- Spin noise spectra revealed the external magnetic field and the Overhauser field from optically oriented nuclei.
- An unobserved "optical field" was detected, directed along the light propagation axis.
- The "optical field" sign correlated with the light helicity and was attributed to the optical Stark effect.
Conclusions:
- Spin noise spectroscopy offers novel magnetometric capabilities.
- The optical Stark effect generates a measurable field in n-GaAs microcavities under specific light conditions.
- This finding deepens the understanding of light-matter interactions in semiconductor systems.
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