Weak measurements of the waist of an arbitrarily polarized beam via in-plane spin splitting

Abstract

As an important parameter to determine the transmission characteristics of a Gaussian beam, the beam waist holds a huge impact in laser technology and imaging systems. Although it is necessary to clearly measure the specific value of the beam waist, the traditional measurement steps are complex and easily introduce error in the measurement process. In this work, we propose an effective method using the in-plane spin splitting (IPSS) generated by the photonic spin Hall effect (PSHE) to precisely estimate the beam waist. We establish a highly sensitive propagation model to describe the relationship between the IPSS shifts and the beam waist of an arbitrary linearly polarized light and then combine with the quantum weak measurement system to amplify the IPSS shifts. We reveal that the IPSS shifts are sensitive to the variation of beam waists when the beam is reflected near the Brewster angle. With the huge amplified IPSS shifts (maximum of 1500 microns), the variation of beam waist can be accurately detected, even by propagation amplification alone. Prospectively, our scheme may provide an effective method for accurately determining the Gaussian beam waist of arbitrary polarization.

Weak-value technique for detecting weak magnetic field based on Faraday magneto-optic effect

“…Finally, the relationship of the shift of the central wavelength 𝛿𝜆 0 and the weak magnetic field can be obtained from Eq. (11). In this paper, the results of our simulation experiment will be shown in the next section.…”

“…In recent years, spurred by fundamental studies of quantum phenomena and by developments in precision measurements [6], Weak-value technique has shown great superiority in numerous high precision measurements, such as amplification of angle rotations [7], longitudinal velocity shifts [6], frequency shifts [8],the Goos-Hanchen shift [9], rotation velocity [10], the photonic spin Hall effect [11]. The "Weak-value" was first proposed by Aharonov et al [12], where information is gained by weakly coupling the probe to the system.…”

Impact of Polarization Phase of Incident Light on In-Plane Spin Splitting of Reflected Beam

“…When the polarization phase is zero, the polarized light at this time is called linearly polarized light. Previous studies on the PSHE mainly focused on the linearly polarized light beam [3], [4], [7], [23]- [27], namely, mainly focused on the polarization angle. The research on impact of polarization phase, as the other important parameter of polarization state, on PSHE is rarely reported [28].…”

Enhancing the sensitivity of amplification of rotation velocity in Sagnac's interferometer with biased weak measurement

“…Normally, SWM is characterized by preparation for the measuring system, a weak interaction between the measuring device(probe) and measured system, post-selection on the system, and a projective measurement on the measuring device to read out the measurement result. Numerous studies show that the quantum measurements with weak value amplification(WVA) can beat the classical schemes with high sensitivity and good robustness, such as amplification of angle rotations [2], longitudinal velocity shifts [4], frequency shifts [3], the Goos-Hanchen shift [5], rotation velocity [6], linear velocity [7] and the photonic spin Hall effect [8].…”