Two-dimensional electronic excitation

R. Osterbacka, C.P. An, X.M. Jiang, and Z.V. Vardeny, Two-dimensional electronic excitations in self-assembled conjugated polymer nanocrystals. Science, 287, 839-842 (2000). 

Osterbacka, R., et al. 2000. Two-dimensional electronic excitations in self-assembled conjugated... 

STUDY OF TRANSPORT AND DEVICES BASED ON THE PHOTO-EXCITED TWO-DIMENSIONAL ELECTRONIC SYSTEM... 

A high mobility two-dimensional electron system exhibits large changes in the resistance, and zero-resistance states, under microwave and Terahertz excitation. We describe associated experimental results and the possibility of using this system as a radiation detector. 

Study of Transport and Devices Based on the Photo-Excited Two-Dimensional Electronic System... 

Description of the excimer photophysics for a two-phase system presented by Wandelt and co-workers [66] are based on both the two-phase model assumptions and the experimental results. The two-phase model describes the results of the experimental studies of photoenergy migration in heterogeneous solid-state polymer blends by Frank and collaborators [68, 69]. Tao and Frank [69] used three-dimensional electronic excitation transport to interpret the ratio of excimer to monomer fluorescence for poly-2-vinylnaphthalene with polycyclohexyl methacrylate. The assumptions of the two-phase model are ... 

Of all potential future applications, the most exciting ones are perhaps those associated with making ferroelectric memories which can be addressed by light or with two-dimensional electronic chips. The idea is to store dielectric information from the three-dimensional bulk into electronic configurations of a two-dimensional chip. The high... 

Plenary 10. Hiro-o Hamaguchi, e-mail address lilrama ,chem.s.u-tokvo.ac.ip (time and polarization resolved multiplex 2D-CARS). Two-dimensional (tune and frequency) CARS using broadband dye source and streak camera timing. Studies dynamic behaviour of excited (pumped) electronic states. Follows energy flow within excited molecules. Polarization control of phase of signal (NR background suppression). 

Straightforward analytical models, however, receive particular attention in the present book, as they are of unique significance in the comprehension of physical phenomena and, moreover, provide the very language to describe them. To exemplify, recall the effect caused on the phase transition theory by the exactly soluble two-dimensional Ising model. Nor can one overestimate the role of the quasiparticle concept in the theory of electronic and vibrational excitations in crystals. As new experimental evidence becomes available, a simplistic physical picture gets complicated until a novel organizing concept is created which covers the facts known from the unified standpoint (thus underlying the aesthetic appeal of science). 

In an effort to understand the mechanisms involved in formation of complex orientational structures of adsorbed molecules and to describe orientational, vibrational, and electronic excitations in systems of this kind, a new approach to solid surface theory has been developed which treats the properties of two-dimensional dipole systems.61,109,121 In adsorbed layers, dipole forces are the main contributors to lateral interactions both of dynamic dipole moments of vibrational or electronic molecular excitations and of static dipole moments (for polar molecules). In the previous chapter, we demonstrated that all the information on lateral interactions within a system is carried by the Fourier components of the dipole-dipole interaction tensors. In this chapter, we consider basic spectral parameters for two-dimensional lattice systems in which the unit cells contain several inequivalent molecules. As seen from Sec. 2.1, such structures are intrinsic in many systems of adsorbed molecules. For the Fourier components in question, the lattice-sublattice relations will be derived which enable, in particular, various parameters of orientational structures on a complex lattice to be expressed in terms of known characteristics of its Bravais sublattices. In the framework of such a treatment, the ground state of the system concerned as well as the infrared-active spectral frequencies of valence dipole vibrations will be elucidated. 

EPMA is a technique for chemically analysing small selected areas of solid samples, in which X-rays are excited by a focused electron beam. Spatial distribution of specific elements can be recorded as two-dimensional X-ray maps using either energy dispersive spectroscopy (EDS) or... 

An electron is confined to a two dimensional square box of side 1 nnt The (a) its minimum energy, and (b) the minimum excitation energy are ... 

In Reference [35], numerical examples of perturbative Sq - S2 excitation and the S2 IC dynamics for the / -carotene are discussed, too. The absence of reliable potential surfaces for this system motivated the use of a minimal two-dimensional model [66], which utilizes a Morse potential in each dimension. All three electronic surfaces Sq, and S2 involved in this example assume the same 2D potential form however, these potentials are shifted to each other. More importantly, in Ref. [35], each potential has 396 bound states in each electronic state within this model, while additionally the S2 and electronic states are coupled by linear coupling. Thus, the Q-space and P-space, as introduced in the context of the QP-algorithm in Section 1.3.1, consist of the S2 and 5 bound states, respectively. 

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