Quantum loss sensing : Comparison between TMSV and the coherent state under a noisy environment

by Sang-il Park (MS Candidate)

Thursday May 19, 2022, 1:30 PM → 2:00 PM Asia/Seoul

119호 (제1과학관)

We theoretically investigate the experimental quantum spectroscopy of plasmonic nanostructures in PRX 4, 011049. In the work, the authors showed that the quan- tum spectroscopy can be more robust against noise than the classical spectroscopy. In the experiment, Photon-number counting measurement was used for the classi- cal spectroscopy, whereas the coincidence counting measurement was used for the quantum spectroscopy. In this work, we consider not only the coincidence counting measurement but also the number difference measurement for the quantum scheme. Our results con- firm the results of the experiment and also explain the main source of the experi- ment. In the PRX, the noise is treated in an asymmetrical way when compared with the classical scheme using the coherent state. We introduce the symmetric setup where the noise is exposed to the same ‘signal’ channel in both the quantum and the classical scheme. We find that the number difference measurement complements the coincidence counting scheme, in that the parameter regimes in which quantum advantages are exhibited are divided between the two measurement schemes. The aforementioned complementary feature still holds, but quantum advantages are less conspicuous. The quantum scheme is more sensitive to the noise introduced to the ’signal’ beam than the idler beam, which the robustness of the quantum scheme.

 

Thesis Advisor: Prof. Chang-Suck No

000000101996_20221120173845.pdf