Universal Scaling Behaviors involved with Superconducting Phase Transitions in High Temperature Superconductivity
* SPEAKERS
Name
Affiliation
E-mail
Sung-Ho Salk
APCTP
* HOST(Applicant)
Name
Affiliation
E-mail
Jihye Jeong
APCTP
sec(at)apctp.org
* DATE / TIME
2014-11-27, 16:00
* PLACE
512 Seminar Room, APCTP Headquarters, Pohang
* ABSTRACT
High temperature cuprate superconductors are distinctively different from low temperature BCS superconductors in that there exist two different energy scales characterized by the nearly linearly decreasing pseudogap temperature and the dome-shaped superconducting transition temperature in the observed phase diagrams. The establishment of relationship between the pseudogap phase and the superconducting phase is utmost important to understand the physics of high temperature superconductivity. Currently, a theory which simultaneously reproduces the distinctive nature of and in the phase diagram is in great demand. Our earlier proposed theoryhas been consistently successful in satisfactorily reproducing not only the dome-shaped phase diagrambut also other important physical properties such as superfluid weight, magnetic susceptibilityand optical conductivity, in agreement with observations. Here we first review and discuss the dome-shaped phase diagram, and then demonstrate inseparability of the dome-shaped superconducting transition temperature from the pseudogap phase. In addition we explain the cause of the invariant value of the optimal doping, around 0.16 in high cuprate oxides. From all of these studies including spin and charge dynamics, we demonstrate that the antiferromagnetic spin fluctuationsinvolving the shortest possible correlation length ( i.e., the nearest neighbor spin dimer) not only coexist in both the pseudogap and superconducting phases but also act as a driving force (prime agent) responsible for the observed high superconductivity, by making coupling with the bosonic charge pairs (holon pairs). We Quantum critical point spotted in the phase diagram will be discussed with a new interpretation of super-symmetry. Lastly but most importantly, not only various universal scaling behaviors in association with the superconducting phase transitions and antiferromagnetic spin fluctuations mentioned above will be convincingly revealed, but also the long-waited cause of invariant optimal doping value at ~ 0.16 is easily verified.
