Jae-Hyeon Eom

Origin of the hump structure in the in-plane optical conductivity of high-TC cuprates based on a SU(2) slave-boson theory

An improved version of SU(2) slave-boson approach is applied to study the in-plane optical conductivity of the two dimensional systems of high Tc cuprates. We investigate the role of fluctuations of both the phase and amplitude of order parameters on the (Drude) peak-dip-hump structure in the in-plane conductivity as a function of hole doping concentration and temperature. The mid-infrared(MIR) hump in the in-plane optical conductivity is shown to originate from the antiferromagnetic spin fluctuations of short range(the amplitude fluctuations of spin singlet pairing order parameters), which is consistent with our previous U(1) study. However the inclusion of both the phase and amplitude fluctuations is shown to substantially improve the qualitative feature of the optical conductivity by showing substantially reduced Drude peak widths for entire doping range. Both the shift of the hump position to lower frequency and the growth of the hump peak height with increasing hole concentration is shown to be consistent with observations.

Origin of peak-dip-hump structure in the in-plane optical conductivity of the high- T C cuprates: Role of antiferromagnetic spin fluctuations of short-range order

An improved U(1) slave-boson approach is applied to study the optical conductivity of the two-dimensional systems of antiferromagnetically correlated electrons over a wide range of hole doping and temperature. Interplay between the spin and charge degrees of freedom is discussed to explain the origin of the peak-dip-hump structure in the in-plane conductivity of high-

Role of spinon in the presence of spinon singlet pair excitations on phase transitions in d -wave superconductors

{T}_{C}

Role of Antiferromagnetic Fluctuations in High Temperature Superconductivity

cuprates. The role of spin fluctuations of short-range order (spin singlet pair) is investigated. It is shown that the spin fluctuations of the short-range order can cause the midinfrared hump, by exhibiting a linear increase of the hump frequency with the antiferromagnetic Heisenberg coupling strength.

Optical conductivity for the two-dimensional systems of strongly correlated electrons

We examine the roles of massless Dirac spinon and spin singlet pair excitations on both quantum and classical phase transitions in extreme type-II d-wave superconductors. We discuss that the massless Dirac fermion (spinon) excitations in the presence of the spin singlet pair excitations do not alter the nature of the quantum phase transition at

DEPENDENCE OF MAGNETIC SUSCEPTIBILITY ON THE NEXT NEAREST HOPPING TERM FOR HIGH TC CUPRATES

T=0,

Scaling behavior in the optical conductivity of two-dimensional systems of strongly correlated electrons based on the U(1) slave-boson approach to the t-J hamiltonian

that is, the XY universality class, while at finite temperature they are seen to induce an additional logarithmic interaction potential between vortices, further stabilizing vortex-antivortex pairs at low temperature for

Invariant Physical Properties in High Temperature Superconductivity

\mathrm{KT}

Quantum phase transitions in

transition for lightly doped high-

d-wave

{T}_{c}