Electrical characteristics of HoBa2Cu3O7 − x-PrBa2Cu3O7 − y-HoBa2Cu3O7 − x junctions with planar-type structures

Small-polaron variable-range hopping in quasi-twodimensional materials: application to PrBa2Cu3-xGaxO7-y

“…In equation (19), L is a logarithmic factor, s and q are numerical factors, N 0 is the two-dimensional concentration of donor sites, and¸is the magnetic length de® ned as¸h /qH 1 /2 . On the other hand our theory gives a T 1 /3 power law and our theoretical ® tting with these data is consistent with other work in the literature (Kabasawa et al 1992, Singh et al 1994a,b, 1996, van Ancum et al 1995a,b, Singh and Thompson 1996, Thompson and Singh 1997, 1998. Therefore, we shall try to explain the low-temperature T < 150 K data of Xu and Guan by using the electron VRH theory for QTD systems given by Thompson and Singh (1997).…”

“…The magnitude of the DOS near x 0 has the same order of magnitude as reported in the literature (Kabasawa et al 1992, Singh et al 1994a,b, 1996, van Ancum et al 1995a,b, Singh and Thompson 1996, Thompson and Singh 1997, 1998. One can see that the DOS decreases with increase in the Ga concentration.…”

“…Recent experimental and theoretical studies in PBCO (Kabasawa et al 1992, Singh et al 1994a,b, 1996, van Ancum et al 1995a,b, Singh and Thompson 1996, Thompson and Singh 1997, 1998 indicate that this compound behaves as a QTD system rather than as a three-dimensional system. The electron conduction takes place mainly in the CuO 2 planes.…”

“…Since the discovery of high-temperature superconductivity, there has been considerable interest in the transport properties of the 123 compound PrBa 2 Cu 3 O 7 y (PBCO) (Kabasawa et al 1992, Xu and Guan 1993, Triberis et al 1994, Singh et al 1994a,b, van Ancum et al 1995a,b, Singh and Thompson 1996, Thompson and Singh 1997. It is very similar to the popular YBa 2 Cu 3 O 7 y superconductor but remains non-superconducting at all temperatures.…”

Small-polaron variable-range hopping in quasi-two- dimensional materials: Application to PrBa2Cu3-<i>x</i>Ga<i>x</i>O7-<i>y</i>

“…Since the discovery of high-temperature superconductivity. there has been considerable interest in the transport properties of the 123 compound PrBa2Cu30,_,, (PBCO) (Kabasawa et a/. 1992, Xu and Guan 1993, Triberis et al 1994, Singh et al 1994a,b, van Ancum et al 1995a,b.…”