Review on Bi–Sr–Ca–Cu–O whiskers

Abstract

We review the current status of the growth, characterization and applications of Bi-Sr-Ca-Cu-O (BSCCO) whiskers from the materials science point of view. Our analysis leads to the conclusion that reconsideration of the importance of the whisker studies is necessary; whiskers can play a major role in studies of the growth mechanism and defects, properties control and their understanding, and new devices and applications. Arguments favourable to the idea that BSCCO whiskers can possibly have a significant impact on future synthesis of nano-objects in this system or other high-T c superconducting systems, as well as in investigation and understanding of the growth processes under elevated magnetic fields, are discussed. Emphasis is made on superconducting whiskers, but non-superconducting ones are also briefly addressed.

Analysis of magnetization loops of electrospun nonwoven superconducting fabrics

“…The j c0 values of the Bi-2212 nanowires were estimated to decrease from 1.69 × 10 7 A/cm 2 to 7 × 10 6 A/cm 2 as T increases from 5 to 30 K. At the same temperature range, the J c0 values of the ultraporous nonwoven fabric decrease from 10.4 × 10 6 A/cm 2 to 2.5 × 10 6 A/cm 2 . Many experiments with Bi-2212 whiskers [43] give the intragrain critical current density similar to values in the sixth column of Table I. At the same time these values are a few orders of magnitude greater than the transport critical current density of Bi-2212 wires [44] that is strongly limited by weak-linked grain boundaries.…”

The single crystal superconducting Bi-2212 whiskers fabrication and their thermal transport properties

“…Different growth techniques such as direct growth from stoichiometric powder/pellet samples by controlled heating or using a flux agent both in the powder or glass precursors have been used to fabricate the BSCCO (Bi-2212) whiskers [6,[7][8][9][10]. Although whisker growth is observed in all the fabrication techniques, the longest single crystal whiskers (∼20 mm long 100-200 m wide and 50-900 nm thick materials) can be obtained only by glass precursor method, compared to other fabrication techniques.…”

“…The Bi-2212 whiskers, obtained by glass precursor method, show the T c value between 80 and 95 K and the critical current density, J c , value of ∼7 × 10 6 A/cm 2 [10][11][12][13][14]. Different elements have been substituted and/or doped to investigate the superconducting properties and growth of whiskers [15][16][17][18][19][20].…”

Control of the oxygen doping in Bi-2212 whiskers by means of their synthesis process

“…Many mechanisms have already been proposed for their growth so far, as summarized in the review by Badica et al [10]. Among the already performed experiments, many studies investigated the influence of the synthesis temperature, especially from the point of view of its relationship with the precursor cationic composition [11][12][13][14][15].…”

“…However, all of them were much more focused on the amount and length of the produced material than on its structural and electronic properties, so that a clear understanding of their correlation with the synthesis temperature is presently lacking [10].…”