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We have exploited angle-resolved photoelectron spectroscopy (ARPES) to study the electronic structure of single crystal samples of high T-c material Bi2Sr2CaCu2O8+delta and of the antiferromagnetic insulator Sr2CuO2Cl2. As one moves away from optimal dopin ...
We used thermal neutron irradiation to produce disorder in Bi-2212 single crystals (T-c = 85 K), at a constant carrier density. The irradiated samples were insulators. High-temperature superconductivity with a lower T-c than prior to irradiation could be r ...
The reflectivity of TmS single crystals has been measured between 3 meV and 12 eV at room temperature and at 6 K, Besides 3p(6)-5d interband transitions a plasma edge due to free carriers is observed. In the middle infrared (near 50 meV) two sharp lines ar ...
Photoelectron spectroscopy with high-energy resolution has been utilized to investigate the charge-density wave (CDW) in 1T-TaS2 between 20 and 360 K. Constant binding-energy curves reveal discontinuities in the temperature dependence of the photoelectron ...
Angle-resolved photoemission spectra taken with high energy resolution on the one-dimensional compound (TaSe4)2I confirm the suppression of the spectral intensity at the Fermi edge for one-dimensional systems and lend support to correlation effects as its ...
Photoelectron spectroscopy reveals a striking correspondence between charge-density-wave-related phase transitions and modifications of the electronic structure in 1T-TaS2. High-energy-resolution spectra indicate that the collapse of the Fermi surface is a ...
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 ...
We measured at high energy and angular resolution the spectral width of photoemission features near the Fermi energy for Ag(100) and for the nearly-two-dimensional metal 2H-NbSe2. The results do not agree with the quadratic width-energy relationship predic ...
Angle-resolved photoemission data taken on some Bi2Sr2CaCu2O8+y single crystals exhibit the formation of a superconducting gap in the absence of a quasiparticle normal state band. We observe the opening of the superconducting gap in the same regions of the ...
We present a simplification of Lieb's proof of the flux phase conjecture for interacting fermion systems--such as the Hubbard model--at half-filling on a general class of graphs. The main ingredient is a procedure which transforms a class of fermionic Hami ...
