Interlayer electrodynamics of Bi2Sr2CaCu2Oy from the c-axis complex dielectric constant measurements

Microwave conductivities of high-Tcoxide superconductors and related materials

“…They proposed that the c-axis QP conductivity, σ c QP , was proportional to the line width of the Josephson plasma resonance (JPR), based on a simple description using the two-fluid model. They measured the linewidth of JPR for the underdoped BSCCO (T c = 82.5, 77.2, and 68 K), and concluded that σ c QP remained suppressed to a small value even in the superconducting state,which was qualitatively similar to the result in BSCYCO [144]. This method has also been applied to the optical reflectivity measurements for Tl 2 Ba 2 CuO 6 and Tl 2 Ba 2 CaCu 2 O 8 thin films [168].…”

“…They found that λ c is rather flat (roughly ∼T 2 ) at low temperatures, while the T linear behaviour was seen in λ a and λ b . The T 2 behaviour in λ c has been seen in LSCO [86], YBCO [91,94,143], and BSCCO [144], remarkably independent of a wide range of materials with different anisotropies.…”

“…One possible source of the increase was a misalignment effect. However, it is probably not important, since a heavily underdoped Bi 2 Sr 2 Ca 0.8 Y 0.2 Cu 2 O y (BSCYCO) (T c = 52 K) shows a monotonically decreasing σ c 1 (T ) with decreasing temperature [144]. They concluded that the behaviour of σ c 1 (T ) was dependent on the hole concentration, and that the large increase observed in the slightly underdoped BSCCO had an intrinsic origin.…”