We deduce easily the coherent term of quantum dynamical model ( the off - diagonal of reduced density matrix ) by improving the nature of displace operator and the nature of coherent states . then , the interaction is energies of a two - photon mechanism and the usual one - photon or liner driving mechanism . we deduce the coherent term by improving the nature of squeezing operators , displace operators and canonical transformation 其一,仅有阻尼相互作用和势能相互作用,此时利用位移算符的性质和相干态的性质很方便地推导了量子动力学模型的相干项(约化密度矩阵的非对角元) ;其二,考虑的是既有单光子相互作用又有双光子相互作用,这时利用相干态、压缩算符及正则变换等的性质推导出相干项。
On the one hand , we deduce the off - diagonal term of reduced density matrix is inner - product of two coherent states and we carry out decoherence in macroscopic limits in two special case , on the other hand , we delay decoherent time by controlling the interaction coefficient . in other part , we define two kind independent phase operators by improving two - mode squeezing coherent states in two - mode phase space and resolve their eigenstates 在第二部分中,我们在双模相位空间里利用双模压缩相干态所对应的算符定义二类独立的相位算符并相应求出本征态,而它的产生算符和湮灭算符是通过简谐振子的产生算符和湮灭算符经过正则变换得到的。