Optics of spin-noise-induced gyrotropy of an asymmetric microcavity

Abstract

The optical gyrotropy noise of a high-finesse semiconductor Bragg microcavity with an embedded quantum well (QW) is studied at different detunings of the photon mode with respect to the QW exciton resonances. A strong suppression of the noise magnitude for the photon mode frequencies lying above exciton resonances is found. We show that such a critical behavior of the observed optical noise power is specific to asymmetric Fabry-Perot resonators. As follows from our analysis, at a certain level of intracavity loss, the reflectivity of the asymmetric resonator vanishes, while the polarimetric sensitivity to the gyrotropy changes dramatically when moving across the critical point. The results of model calculations are in a good agreement with our experimental data on the spin noise in a single-quantum-well microcavity and are confirmed also by the spectra of the photoinduced Kerr rotation in the pump-probe experiments.

Spin noise explores local magnetic fields in a semiconductor

“…1b . The details about the sample and the experimental setup can be found in refs 20 , 21 , 25 and in Methods section. In our experiments the wavelength of the probe nm beam corresponded to the region of nominal transparency of the sample, λ > λ g , where λ g ≈ 820 nm corresponds to the fundamental absorption edge of GaAs.…”

Raman scattering model of the spin noise

“…Not only spin carrier Larmor precession in volume ( [9,15] etc.) and low-dimensional media (e. g. [16,17]) can be addressed by SNS, but also the nuclear dynamics [18][19][20], light-matter interaction effects [21,22], spatial properties distribution [23,24], and even noise of valley redistribution of electrons [25]. Still the atomic systems attract the significant attention of researchers [26][27][28][29][30][31][32][33] as model objects which allow to reveal the fundamental pecularities of spin noise formation mechanics.…”

Increased sensitivity of spin noise spectroscopy using homodyne detection in n -doped GaAs

“…In general, the angle of Faraday rotation is proportional to the optical path length, which can be increased by placing the active medium into a cavity, either a macroscopic one [16] or a microcavity [17][18][19]. Another method to increase the spectroscopic sensitivity is to increase the probe intensity sent through the sample while keeping the photon flux incident on the photodetector at a low level by diminishing the light intensity using a high polarization extinction (HPE) geometry [20].…”