Photon mode

Comparison between heat-mode and photon-mode processes is given in Table I. The main differences are the superior resolution and the possibility of multiplex recording in photon-mode systems. Because of the diffusion of heat, the resolution of heat-mode recording is inferior to that of photon-mode systems. Furthermore, photons are rich in information such as energy, polarization and coherency, which can not be rivalled by heat-mode recording. 

Table I. Comparison between heat- and photon-mode image recording...

Research on liquid crystalline polymers(LCP) is a fashionable subject with the goal of developing speciality polymers of superior mechanical and thermal properties. Besides these properties, other interesting properties of LCP have not been fully utilized. We are trying to use thermotropic LCP for photon-mode image recording material. 

Barnes WL (1998) Fluorescence near interfaces the role of photonic mode density. J Mod Opt 45 661-699... 

The intriguing properties of devices made by the combination of a film-forming dye and an optical microstructure turn up in the discovery of strong coupling between excited states and photon modes in microcavities, creating Rabi-splitted polariton modes [211]. They occur in materials with narrow absorption bands (e.g., porphyrins and cyanine dyes) and may pave the way to new laser types and fundamental insights into the interaction of matter and light. 

This is a burgeoning area of research and it is now obvious that this type of work holds out the potential for molecular computers and neural networks using photon mode input (see also Chapter 5, section 5.7). ... 

The next stages in the development beyond 20 Gb will be to move away from heat mode recording to photon mode recording. This is discussed elsewhere in this book, under photochromies (Chapter 1, section 1.2.8.3) and under holography, optoelectronics and photonics in Chapter 5. 

The 0(3) quantum electrodynamic equivalent of the RFR effect has been numerically analyzed by Crowell [17] using the Hamiltonian (327). Numerically, it is possible to consider only a finite number of photon modes, and the difference in energy between these modes is set equal to the difference between the two spin states of the fermion. More complex situations were also analyzed... 

Kitzerow et al. recently demonstrated that temperature-induced phase transitions (Iso-N) and electric field-induced reorientation of a nematic liquid crystal (5CB in this case) can be used to tune photonic modes of a microdisc resonator, in which embedded InAs quantum dots serve as emitters feeding the optical modes of the GaAs-based photonic cavity [332],... 

Achieved NotoI °pi>cal memory, photon-mode spatial light modulation, ulttafast optical parallel switching, optical enhancement of nonlinear optical properties, etc... 

A. Photon-Mode Superresolution by Transient Bleaching of Phthalocyanines... 

Figure 26 (a) Schematic representation of photon-mode superresolution using transi-... 

The great merit of thermal irreversibility is the permanent nature of the states. Therefore, fulgides have long been viewed as potential candidates for photon-mode optical recording materials. In addition, fulgides have been used as prototypes to demonstrate their potential applicability as photoswitchable functional materials. Those switch models that had appeared up until the end of 1999 are described in this chapter. 

Note that the quantum limit on coherent receivers is 0.5hv/k or 0.024 K/GHz (Wright, 1999). This corresponds to 0.5 photons per mode. The 0.3 K/GHz for cryogenic HEMTs is about 7 photons/mode. At 72 GHz the CMB has only n = 0.4 photons per mode, where n = (exp[hv/kT] — l)-1 is the mean number of photons per mode. Thus a background-limited incoherent detector could be much more sensitive than a coherent radiometer using HEMTs. 

This split-off discrete state rejoins, for cK co0, the exciton energy ha>0 it behaves qualitatively in the same way as the lower branch of the 3D polariton.33 35 For this reason we call it the 2D polariton. It is the projection of the exciton K> on this 2D polariton (radiatively stable) that constitutes (1) the finite limit value of the curves AK t) for t- oo (Fig. 3.8), and (2) the weight of the discrete peak in the spectrum PK((o) (Fig. 3.9). The transition, in the 2D polariton branch, between the photon and the pure exciton characters occurs around the value K0 = co0/c in an area of width AK = r0/c (with ro = 15cm 1). Thus, the 2D polariton may be considered as a photon mode trapped in the 2D lattice, where it acquires its own dispersion.115,116,126 Therefore, the 2D polaritons cannot be excited by free photons, but they may be coupled to evanescent waves, by ATR for example.115,116... 

F. Matsui, H. Taniguchi, Y. Yokoyama, K. Sugiyama, and Y. Kurita, Application of photochromic 5-dimethylaminoindolyl fulgide to photon-mode erasable optical memory media with non-destructive ability based on wavelength dependence of bleaching quantum yield, Chem. Lett., 1994, 1869-1872. 

The color species developed by near-UV light are hardly affected by irradiation with visible light, suggesting that the back electron transfer is thermal in nature. This is promising for photo-memory, that is, color development by photon-mode and heat-mode bleaching. 

Radiative decay engineering file role of photonic mode density in biotechnology. Anal. Biochem. 36(14) R240-R249. 

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