Study On Gaussian Quantum Correlation Method In Cell Temperature Measurement And Related Problems

The establishing of quantum mechanics promoted the development of other disci-plines,and gave birth to new disciplines such as quantum information,quantum chem-istry and quantum biology.The presence of quantum correlations is one of the main features of quantum mechanics in multipartite quantum systems.Among the quantum correlations,the entanglement is surely the most important one,but non-entangled quantum correlations are also proved to be important physical resource.As a matter of fact,non-entangled quantum correlations not only play important roles in various quantum computing tasks and quantum communications,but also widely exist in var-ious biological activities,such as photosynthesis and the magnetic field navigation of birds.Many studies show that quantum correlations also have inestimable application prospect in biomedicine.In order to identify if a given system contains quantum corre-lation and quantify the amount of the correlation,the study and the characterization of quantum correlations that go beyond the paradigm of entanglement had attracted more and more attention recently.By far,the estimate of the quantum correlation and its quantization,i.e.the degree of quantum correlation,is very hard,which limits the practical application of quantum correlation.To find quantum correlation that is easy to estimate,hence easy to apply,based on fidelity,we propose two quantum correla-tions induced by invariant unitary operation for continuous variable systems,investigate their properties and computational issues,and propose a Quantum correlation method in cell temperature measurement.The main results of this dissertation are described as follows:1.Based on Uhlmann fidelity,we propose a quantum correlation NFg for bipartite continuous-variable systems,and study its properties.We prove that NFg is a rem-edy for the local ancilla problem associated with the geometric measurement-induced correlations;is local Gaussian unitary invariant;is non-increasing under any Gaussian quantum channel performed on the non-measured subsystem;and is an entanglement monotone when restricted to pure Gaussian states.A way to estimate NFg for general Gaussian states is given,and a concrete formula for(1+1)-mode symmetric squeezed thermal states(SSTSs)is presented.By comparing NFg,A with other quantum correla-tions such as Gaussian quantum discord and Gaussian geometric discord in scale,we reveal that NFg,A is a quantum correlation with better property.2.Compared with other known quantum correlations,NFg is easer in computation,but,the estimation of NFg is still complicated.Hence,we propose a nonclassical correla-tion NFg for bipartite continuous-variable systems based on Yu's fidelity.Its properties are studied,and computation formulas are given for Gaussian states.The comparison between NFg and other known quantum correlations for Gaussian states suggests that NFg is better in application.Moreover,we find that this kind of quantum correlation does not increase after performing local Gaussian channel on the unmeasured subsys-tem for(1+1)-mode Gaussian states,and we believe this property holds for multi-mode bipartite Gaussian states as well.3.During the process of estimating the correlation NFg,an upper bound M is found,which only relies on the CM of the given Gaussian states.This upper bound M is easy to estimate for any(n+m)-mode Gaussian states,consumes less physical resource since it is independent of the local measurements and optimization process.We study the properties of the upper bound further,find that M is relative stable,is ancilla problem free and locally Gaussian unitary invariant.Furthermore,M does not increase when perform Gaussian channels on both subsystems for(1+1)-mode Gaussian states,and can play a better role in its application.4.Intracellular temperature affects physiological processes and biochemical re-actions in cells.The determination of intracellular temperature is a key point in life science,and may Applied in clinical medicine in future.In this dissertation,by using the evolution behavior of quantum correlation M in thermal environment,we propose a quantum way to detect cell temperature and mitochondria.5.Lazy states contain quantum correlation differ from quantum entanglement,and quantum correlations outside the entanglement wildly exists in Life phenomena.We establish some ways to identify lazy states and discuss the relations between lazy states and other quantum correlations.By using our method,it is easy to determine if the Polymer states in Photosynthesis contain quantum correlations other than entan-glement.The quantum correlations based on fidelity and its upper bond proposed in this dissertation are easy to estimate and have no ancilla problem,can be used to study quantum phenomena and mechanisms of biological phenomena.can serve as theoretical tools for the study of quantum associations in biological systems.Further,One can use Gaussian quantum correlation as a tool,to develop quantum correlation technology,and apply it in biomedicine.