We systematically study the role of Weyl cone tilting in the spin Hall effect of light (SHEL) in doped Weyl semimetals (WSMs), and propose a new scheme to determine the type of a WSM and to sense the tilt degree of Weyl cones precisely. It is found that in the case of a small amount of doping, the SHEL in type-I WSMs shows almost no dependence on the tilt degree of Weyl cones, while the SHEL in type-II WSMs is extremely sensitive to variations in the degree of tilt. However, in the case of a large amount of doping, not only the SHEL in type-II WSMs but also the SHEL in type-I WSMs show strong dependences on the tilt degree. These trends are mainly attributed to the variation of the real part of the Hall conductivity with the tilt degree. Remarkably, by using a quantum weak measurement, the tiny SHEL shifts can be amplified and detected to a desirable accuracy. Based on the obviously different tilt-dependent characteristics of amplified SHEL shifts in WSMs, we propose a new scheme to determine the type of a WSM and to sense the tilt degree precisely. By adjusting the doping level, the sensing sensitivity can reach up to 1461.55 µm per degree of tilt. This study may provide an application reference for the fabrication of WSM parameter sensors and other topological photoelectric devices.

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We propose a high-resolution scheme for determining the kinetic parameters of sucrose hydrolysis based on the weak measurement, and the parameters including rate constant, half-life, activation energy and pre-exponential factor are experimentally determined. In the scheme, the postselection state of weak measurement is modified by the optical rotation angle in the process of sucrose hydrolysis, and the amplified spin-Hall shift acts as a probe for determining the kinetic parameters. The rate constant and half-life are obtained based on the time variations of amplified spin-Hall shifts under different reaction conditions of temperatures and hydrochloric acid concentrations. The corresponding activation energy and pre-exponential factor are also evaluated for explaining the physical mechanism which influences the rate constant and analyzing how to adjust the reaction conditions to predict or control the rate. The high resolution for optical rotation angle is achieved in our scheme, which can reach 4.9 × 10 −4 degree with one order of magnitude improvement over the polarimeter. These results can provide a possibility for the determination of chemical kinetic parameters with high-precision, real-time, label-free and convenient effects.

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