Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userChiral Optical Absorption by a Vortex in p_x pm i p_y-Wave Superconductor
75
0
0.0
(
0
)
Added by
User SpmmatuMasashige Matsumoto
Publication date
1999
fields
Physics
and research's language is
English
Authors
Masashige Matsumoto
Ask ChatGPT about the research
No Arabic abstract
The chiral optical absorption by a single vortex in a p_x pm i p_y-wave superconductor is studied theoretically. The p_x pm i p_y-wave state was recently suggested as the symmetry of the order parameter of Sr_2 Ru O_4 superconductor. Due to the violation of time reversal symmetry, there are two types of vortices whose winding orientation is the same or opposite to the angular momentum of the Cooper pair. In a real material domains with p_x pm i p_y-wave states are expected. However, optical absorption of circular polarized light depends only on the winding of the vortex and has a low energy absorption peak which results in dichroism. Dichroism occurs if superconductivity is realized on a single Fermi surface sheet. However, in the case of several Fermi surface sheets dichroism may disappear, if the both types of carriers are present, electron-like and hole-like. Therefore chiral optical absorption is a possible experiment to detect the orbital dependent superconductivity which was suggested as the superconducting state of Sr_2 Ru O_4.
rate research
Read More
Quasiparticle states around a single vortex in a $p_xpm i p_y$-wave superconductor are studied on the basis of the Bogoliubov-de Gennes (BdG) theory, where both charge and current screenings are taken into account. Due to the violation of time reversal symmetry, there are two types of vortices which are distinguished by their winding orientations relative to the angular momentum of the chiral Cooper pair. The BdG solution shows that the charges of the two types of vortices are quite different, reflecting the rotating Cooper pair of the $p_xpm i p_y$-wave paring state.
The electronic states near a surface or a domain wall in the p_x pm i p_y -wave superconductor are studied. This state has been recently suggested as the superconducting state of Sr_2 Ru O_4. The p_x pm i p_y-wave paring state breaks the time reversal symmetry and induces a magnetic field. The obtained temperature dependence of the magnetic field is consistent with the observed mu SR data.
The study of superconductivity with unconventional order is complicated in condensed matter systems by their extensive complexity. Optical lattices with their exceptional precision and control allow one to emulate superfluidity avoiding many of the complications of condensed matter. A promising approach to realize unconventional superfluid order is to employ orbital degrees of freedom in higher Bloch bands. In recent work, indications were found that bosons condensed in the second band of an optical chequerboard lattice might exhibit p_x pm i p_y order. Here we present experiments, which provide strong evidence for the emergence of p_x pm i p_y order driven by the interaction in the local p-orbitals. We compare our observations with a multi-band Hubbard model and find excellent quantitative agreement.
The electronic states near a surface or a domain wall in the p-wave superconductor are studied for the order parameter of the form p_xpm i p_y-wave, which is a unitary odd-parity state with broken time-reversal symmetry. This state has been recently suggested as the superconducting state of Sr_2 Ru O_4. The spatial variation of the order parameter and vector potential is determined self-consistently within the quasi-classical approximation. The local density of states at the surface is constant and does not show any peak-like or gap-like structure within the superconducting energy gap, in contrast to the case of the d-wave superconductors. The influence of an external magnetic field is mainly observable in the energy range above the bulk gap. On the other hand, there is a small energy gap in the local density of states at the domain wall between domains of the two degenerate p_x+i p_y-wave and p_x-i p_y-wave states.
Much excitement surrounds the possibility that strontium ruthenate exhibits chiral p-wave superconducting order. Such order would be a solid state analogue of the A phase of He-3, with the potential for exotic physics relevant to quantum computing. We take a critical look at the evidence for such time-reversal symmetry breaking order. The possible superconducting order parameter symmetries and the evidence for and against chiral p-wave order are reviewed, with an emphasis on the most recent theoretical predictions and experimental observations. In particular, attempts to reconcile experimental observations and theoretical predictions for the spontaneous supercurrents expected at sample edges and domain walls of a chiral p-wave superconductor and for the polar Kerr effect, a key signature of broken time-reversal symmetry, are discussed.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
