Locating the pseudogap closing point in cuprate superconductors: Absence of entrant or reentrant behavior

Jeffery L. Tallon; James G. Storey; John R. Cooper; John W. Loram

doi:10.1103/PhysRevB.101.174512

← Back to search

Locating the pseudogap closing point in cuprate superconductors: Absence of entrant or reentrant behavior

Jeffery L. Tallon, James G. Storey, John R. Cooper, John W. Loram

DOI 10.1103/PhysRevB.101.174512 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

Many current descriptions of the pseudogap in underdoped cuprates envision a doping-dependent transition line T*(p) which descends monotonically toward zero just beyond optimal doping. There is much debate as to the location of the terminal point p* where T*(p) vanishes, whether or not there is a phase transition at T* and exactly how T*(p) behaves below Tc within the superconducting dome. One perspective sees T*(p) cutting the dome and continuing to descend monotonically to zero at p*≈0.19 holes/Cu—referred to here as entrant behavior. Another perspective derived from photoemission studies is that T*(p) intersects the dome near p≈0.23 holes/Cu then turns back below Tc, falling to zero again around p*≈0.19—referred to here as reentrant behavior. By examining field-dependent thermodynamic data for Bi2Sr2CaCu2O8+δ we show that neither entrant nor reentrant behavior is supported. Rather, p* sharply delimits the pseudogap regime: For p<0.19 the pseudogap is always present, independent of T. Similar results are found for Y0.8Ca0.2Ba2Cu3O7−δ. For both materials, T*(p) is not a temperature but a crossover scale, ≈E*(p)/2kB, reflecting instead the underlying pseudogap energy E*(p) which vanishes as p→p*≈0.19.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Bi2Sr2CaCu2O8+δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Y0.8Ca0.2Ba2Cu3O7-δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi2.1Sr1.9CaCu2O8+δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi2.1Sr1.9Ca0.7Y0.3Cu2O8+δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi1.8Pb0.3Sr1.9CaCu2O8+δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Ba(Fe1-xCox)2As2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Ba1-xKxFe2As2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
PrOs4Sb12 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Tl2Ba2CuO6 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi2Sr2CuO6 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown