Study Of Casimir And Casimir-Polder Free Energy In Microcavity

At the onset of the 20th century,the study of the spectral behaviour of blackbody radiation has inspired the quantization of the electromagnetic field.It also inevitably led to the recognition of the existence of zero-point energy,the so called vacuum fluctuations.Vacuum fluctuations are ultimately responsible for spontaneous emission of the atom and the anomalous magnetic moment of the electron and Lamb shift.In a ‘hot' vacuum,They all exhibit a temperature dependence.Similarly,the fluctuations of the quantum vacuum can lead to Casimir effect.60 years ago,Casimir found that two neutral,perfectly conducting plates,experience an attractive force in vacuum.This phenomenon,known as Casimir effect.In the same year,Casimir and Polder found the existence of an attractive force between a perfectly conducting plane and a neutral atom in vacuum,which is called Casimir-Polder force.Casimir-Polder force and Casimir effect are purely quantum phenomena.They are all induced by different boundary conditions in different materials and vacuum fluctuations.They strongly depends on the geometry of the boundaries among others aspects,such as the geometry and topology of the manifold.Very recently,Casimir experiments with ferromagnetic Ni surfaces have been carried out.Numerous geometries of the surfaces have been probed,and it has been demonstrated that the magnitude of the Casimir force can be controlled by fabricating surfaces with nanoscale corrugations,a result which opens the way to novel nanotechnological applications of the Casimir effect.At the same time,the effect of temperature on the Casimir effect and Casimir-Polder force has always been a hot issue in study.In the paper,I review the research about the Casimir effect and the Casimir-Polder force briefly.Then applying the thermal field dynamics theory and the perturbation theory,we study the effect of temperature on the Casimir energy in a cavity comprising a dielectric with output coupling,obtain the Casimir free energy of the cavity and then calculate the low and high temperature situation.On this basis,We study the the contribution of the temperature and the higher order term to the atom-wall Casimir-polder energy in a maser cavity,then we calculate the Casimir-polder free energy of the cavity.Finally we summarize the full work and point out the reasonable outlook of our future researches.