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We show that one-dimensional quantum systems with gapless degrees of freedom and open boundary conditions form a universality class of quantum critical behavior, which we propose to call ''bounded Luttinger liquids." They share the following properties wit ...
Dispersing 1D bands have been observed for the first time in an organic conductor by high resolution photoemission experiments on TTF-TCNQ (tetrathiafulvalene-tetracyanoquinodimethane). Their properties are extremely unusual: the bandwidth is much larger t ...
We consider a design approach to reduce unwanted zero-order intensity due to profile depth error in diffractive elements. Our method is based on addition of local bias phase to a binary element phase, leading to the introduction of a third phase level. We ...
Novel design of an integrated digital refelction-type phase shifter based on a Barium Strontium Titanate thin-film capacitor is presented. Measured characteristics of the phase shifter am compared with the theoretically predicted ones. ...
A clear signature of enhanced backscattering of excitons is observed in the directional resonant Rayleigh scattering of light from localized two-dimensional excitons in disordered quantum wells. Its spectral dependence and time dynamics are measured and th ...
We review some recent spectroscopic results on low-dimensional systems, including high-T-c superconductors, and charge density wave compounds. We briefly discuss the reasons for the present interest in these materials, and the relevance of band mapping exp ...
High-resolution angle-resolved photoemission and core-level photoemission measurements were performed on single crystal samples of the quasi-one-dimensional material (TaSe4)(2)I and the cuprate superconductor Bi2Sr2CaCu2O8+x. Resistivity measurements were ...
We have exploited angle-resolved photoelectron spectroscopy to study changes in the quasiparticle excitations of CuO2 planes as a function of the carrier density, in optimally doped and underdoped Bi2Sr2CaCuO8+x and in Sr2CuO2Cl2. We have observed large ch ...
The dynamics of intersubband relaxation in GaAs quantum wells and the role of hot carriers and the phonon distributions have been investigated using two different optical techniques with femtosecond resolution: 1) time-resolved photoluminescence and 2) pum ...