Optimal preselection and postselection in weak measurements for   observing photonic spin Hall effect
  Photonic spin Hall effect (SHE) holds great potential applications in precision metrology. How to obtain a high measurement precision is an important issue to detect the photonic SHE. In this letter, we propose using optimal preselection and postselection in weak measurements to enhance the measurement precision. We find that the maximum weak value and pointer shift can be obtained with an optimal overlap of preselection and postselection states. These findings offer the possibility for improving the precision of weak measurements and thereby have possible applications for accurately characterizing the parameters of nanostructures. 
Xinxing Zhou, Xing Li, Hailu Luo, and Shuangchun Wen
physics.optics quant-ph