Optical amplification of spin noise spectroscopy via homodyne detection

TL;DR

This paper demonstrates a homodyne detection method for spin noise spectroscopy that achieves shot noise limited measurements, enabling more sensitive studies of delicate semiconductor spin systems like quantum dots.

Contribution

It introduces a homodyne detection technique for spin noise spectroscopy that overcomes electronic noise limitations, allowing for more precise measurements in low-frequency regimes.

Findings

Homodyne SN spectroscopy achieves shot noise limited sensitivity.

The method is effective in low-frequency spectral measurements.

Potential applications include advanced semiconductor spin research.

Abstract

Spin noise (SN) spectroscopy measurements on delicate semiconductor spin systems, like single InGaAs quantum dots, are currently not limited by optical shot noise but rather by the electronic noise of the detection system. Here, we report a realization of homodyne SN spectroscopy enabling shot noise limited SN measurements. The proof-of-principle measurements on impurities in an isotopically enriched rubidium atom vapor show that homodyne SN spectroscopy can be utilized even in the low frequency spectrum which facilitates advanced semiconductor spin research like higher order SN measurements on spin qubits.