来源地:以下内容 著者: 发布公告期限:2022-06-04 𒁃
From local thermometry to general quantum multi-parameter global sensing
检测结果人: Dr. Victor Montenegro(网上创新科技学校地基与探索探索院)
报告格式文献综述：Measuring the effective temperature of the oscillator is pe▨rhaps one of the most relevant ste🧸ps in the characterization of quantum optomechanical systems. Conventionally, the cavity is strongly driven, and the overall system is well-described by a Gaussian preserving Hamiltonian. Here, we consider an undriven optomechanical system via non-Gaussian radiation-pressure interaction. We show that the optical probe gets a nonlinear phase, resulting from the non-Gaussian interaction, and undergoes an incoherent phase diffusion process. We propose using a nonlinear Kerr medium before a homodyne detector that enhances the precision to nearly saturate the ultimate quantum bound given by the quantum Fisher information . The above sensing procedure falls into local sensing, namely when the quantum sensor operates efficiently only when the unknown parameters vary within a very narrow region. In the second part of this talk, we present a systematic method for optimizing the sensor to operate with its best precision over any arbitrarily large interval, namely, global sensing. By exploiting quantum many-body probes, our protocol harnesses the criticality for significantly enhancing the precision of multi-parameter estimation, independent of the sensing intervals .
 V. Montenegro, et.al, "Mechanical ꦿoscillator thermometry in the nonlinear optomechanical regime". Phys. Rev. Research 2, 043338 🎀(2020).
 V. Montenegro, et.al, "Global sensing and its impact for quantum many-body probes w♎ith criticality," Phys. Rev. Lett. 126, 200501 (2021).
汇报人百科: Dr. Victor Montenegro, a postdoctoral researcher working at UES🍃TC. Currently, He is working on quantum metrology with quantum optomechanics flavor and many-body physics.