Microscopic theory of quantization of radiation in molecular dielectrics: Normal-mode representation of operators for local and averaged (macroscopic) fields.
Microscopic theory of quantization of radiation in molecular dielectrics: Normal-mode representation of operators for local and averaged (macroscopic) fields.
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分子电介质中辐射量子化的微观理论：局部和平均（宏观）场算子的简正模表示。
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发表时间：
1996
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通讯作者：
Juzeliunas
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作者：
Juzeliunas
辐射的量子化已经在现实分子介质中从第一原理进行，由任意数量的能级（电子，振动，旋转等）表示。每一个组成分子。采用极化激元模型，将场算符展开为极化激元产生和湮灭的正常玻色算符。的膨胀系数已明确推导出的正常模式，其特征在于波长大大超过分子之间的特征距离的分离。因此，形式主义适用于光谱的长波长区域，其中宏观折射率的描述是相关的;此外，考虑仅限于光谱的非吸收区域。该理论已制定的方式，使得有可能平行和比较考虑运营商的平均（宏观）和当地的领域。因此，导出的模式扩展涵盖了当地的位移场运营商和平均（宏观）运营商的电，位移，磁，极化场，和矢量势。的扩展，涉及求和的任意数量的分支的极化激元色散，显然体现了折射的影响。为此，局域场效应内在地出现在系统地处理光子umklapp过程的现有形式主义中。建立了局部场算子和平均场算子的展开分量之间的关系。的关系支持一些以前的尝试连接的局部和宏观场运营商的振幅唯象，也与经典电动力学的熟悉的结果是一致的。已经证明了双时对易关系是保持的，用正常的玻色算子来表示平均场的算子。另一方面，宏观场之间的对易关系与微观场之间的对易关系具有相同的形式，只是服从粗粒化过程。最后，本研究处理的宏观和本地运营商提供了一个工具，结合研究量子化场的传播的分子链，也与嵌入的分子或原子的相互作用的字段。\textcopyright{} 1996美国物理学会。
Quantization of radiation has been performed from first principles in a realistic molecular medium, represented by an arbitrary number of energy levels (electronic, vibrational, rotational, etc.) for each constituent molecule. Adopting a polariton model, the field operators have been expanded in terms of normal Bose operators for polariton creation and annihilation. The expansion coefficients have been derived explicitly for the normal modes characterized by wavelengths exceeding considerably the characteristic distance of separation between the molecules. Accordingly, the formalism applies to the long-wavelength region of the spectrum for which description in terms of the macroscopic refractive index is relevant; furthermore, consideration is restricted to the nonabsorbing areas of the spectrum. The theory has been formulated in a manner that made possible a parallel and comparative consideration of operators for both the averaged (macroscopic) and local fields. Consequently, the mode expansions derived cover both the local displacement-field operator and also the averaged (macroscopic) operators for the electric, displacement, magnetic, and polarization fields, and the vectorial potential. The expansions, involving summation over an arbitrary number of branches of polariton dispersion, manifestly embody the refractive influences as well. To this end, the local-field effects intrinsically emerge within the present formalism that treats systematically the photon umklapp processes. Relations have been established between the expansion components of the local and averaged field operators. The relationships support some previous attempts to link the amplitudes of local and macroscopic field operators phenomenologically, and are also consistent with the familiar results of classical electrodynamics. Equal-time commutation relations have been demonstrated to be preserved, expressing the operators for the averaged fields in terms of the normal Bose operators. On the other hand, the commutation relations between the macroscopic fields are of the same form as those for their microscopic counterparts, subject to the coarse-graining procedure. Finally, the present study dealing with the macroscopic and local operators provides a tool for combined investigation of both propagation of the quantized fields in molecular dielectrics and also interaction of the fields with the embedded molecules or atoms. \textcopyright{} 1996 The American Physical Society.