Light quantization for arbitrary scattering systems

Abstract

We present a quantum theory of light scattering for the analysis of the quantum statistical and fluctuation properties of light scattered or emitted by micrometric and nanometric three-dimensional structures of arbitrary shape. We obtain general three-dimensional quantum-optical input-output relations providing the output photon operators in terms of the input photon operators and of the noise currents of the scattering system. These relations hold also for photon operators associated with evanescent fields, for anisotropic scattering systems and/or for media with a nonlocal susceptibility. We find that the commutation relations of the output photon operators, carrying all the information on the scattering and/or the emission process, result to be fixed by energy conservation and reciprocity. We prove that this quantization scheme is consistent with QED commutation rules by using a novel relationship between vacuum and thermal fluctuations. This theoretical framework has been applied to analyze the spectral density of light close to a point scatterer under different nonequilibrium conditions.

Thermal noise and correlations in photon detection

“…͑7͒ for open electromagnetic scattering systems in which the field is not confined to a finite volume has also been discussed. 52,53 In analogy to the situation for classical thermal noise, the noise operators c i † ͑͒ are necessary if the network or system has loss. As explained in Appendix B, the quantum scattering matrix S ij ͑͒ used in this equation is exactly the same quantity as would be used to describe the classical network or system.…”

Electromagnetic field quantization in a linear polarizable and magnetizable medium

“…Matloob has quantized the macroscopic electromagnetic field in a linear isotropic permeable dielectric medium by quantizing the Langevin equation and associating a damped quantum harmonic oscillator with each mode of the radiation field [10]. There are some other approaches to quantizing the electromagnetic field and interested reader is referred to [11][12][13][14][15][16][17][18][19][20][21].…”

Comment on “Imaging the Local Density of States of Optical Corrals”

“…the light intensity at a point r when the material system is illuminated isotropically and incoherently (e.g by a thermal source [3]). For a point detector polarized along a specific direction u, it can be expressed as whispering gallery modes of a dielectric sphere).…”