Recent important progresses in the filed of HTSCs
Scientists from the USA, China and Japan have studied the Furrier transform scanning tunneling spectroscopy (FT-STS) of Bi-2212 crystals to find the relation between the features of r-space and k-space electronic structures of HTSCs: such as the modulation of the electronic local density of states (LDOS~g(r,ω)) observed by STM, and coherence peak, Fermi surface and [...]
Determining of bosons (phonon or magnetic modes) which play an important role in the electron-boson interaction (EBI) and making pairs in HTSCs has been complicated, because different aspects of experimental evidences such as ARPES and optical spectroscopy could be interpreted by one of these bosons. Recently atomic-resolution STM study of Bi-2212 has been done by [...]
Observed local density of states (LDOS) modulations in the tunneling spectroscopy of HTSCs has started extensive research for determining its origin and consequences: two important possibilities are creation of new electronic order in the pseudogap, or interference of electronic states. To make clearer this subject, a group of scientist from the USA, Japan an Canada [...]
The experimental observations of magnetic induced electronic structure are completely different from the pure d-wave BCS models predictions, for example: the absence of zero bias conductance peak or four-fold symmetric of LDOS (local density of states), low energy quasiparticle states about some meV in a radius of 75 Å, etc. Theories considering strong electronic correlation [...]
Collaboration of the scientists from the United States and Japan has resulted in discovering an incommensurate local ordering in the pseudogap of HTSCs. They have investigated the scanning tunneling microscopy (STM) of the slightly underdoped single crystal of 0.6% Zn-doped Bi2212 (Tc=80 K, pseudogap energy ∆ps~35-40 meV at 100 K). The Fourier analysis of the [...]
Previous studies indicate the appearance of the checkerboard pattern in the pseudogap state of Bi2212 surrounding vortex cores or in strongly underdoped region. Scientists from Japan in collaboration with the United States have made a study to make clearer this situation and its relation with a hidden electronic order in the pseudogap. Existing of some [...]
It is surprisingly interesting that the quantities such as the integrated local density of states (LDOS), tunneling spectrum and superconducting gap which are homogeneous in the conventional BCS superconductors seem to be inhomogeneous on the nanoscale for the HTSCs. Some scientists of the United States and Tokyo University have discussed the details, origin and consequences [...]
The superconducting group at the Princeton University with collaboration of Japanese group has succeeded to measure the superconducting gap on the atomic scale of High-Tc Superconductor Bi2Sr2CaCu2O8+δ (undrdoped, UD, optimaldoped, OP, and overdoped, OV, samples) for different doping concentrations and temperatures. They have determined the gap value and estimate the temperature which the gap is [...]
