The “virgin” curve for microwave magnetoabsorption in micron-size powders of cuprate superconductors

Anomalous hysteresis studies in Bi-2223/Bi-2212 superconductors by non-resonant microwave absorption (NRMA) with special reference to energy stabilized Josephson (ESJ) fluxons

“…On increasing temperature up to 95 K conductors also. The former signal at zero field has been associated both the signals were found to grow in intensity indicating that the with motion of IGBJ fluxons [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Whereas the latter broad hump number of IGBJ fluxons and ESJ fluxons increases as the temperature signal been associated with motion of ESJ fluxons [21b, 30,31].…”

“…In intrinsically granular unconventional high-Tc superconducting materials like cuprates, the magnetization hysteresis due to trapping of magnetic fluxons at various defects has been studied previously by using (1) direct magnetization methods like: DC magnetic field (HDC) variation of (i) flux density (B), (ii) microwave surface resistance (Rs), (iii) transport critical current density (Jc) [1][2][3][4][5][6][7] and (2) modulated magnetic field variation of non-resonant microwave absorption (P) [8][9][10][11][12][13][14][15][16][17][18][19].…”

“…It is striking that, in contrast to the above direct magnetization methods, the magnetic field modulated hysteresis in high-Tc cuprates by non-resonant microwave absorption (NRMA) method [8][9][10][11][12][13][14][15]18,19] has generally shown anomalous nature even at LT/LH. This behavior has also been observed in other variety of superconducting systems like: YPd5B2C0.35/YNi2B2C [20], and MgB2 [21a,22], granules of Nb3Sn, NbGeAl2,V3Si, As, Al, etc.…”

“…[23][24][25][26]. It is surprising that despite the voluminous literature on the NRMA hysteresis [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], only a few groups [11,12,18] have mentioned about its anomalous nature and related it to the most successful model by Ji et al [6] and its modifications by Mahel et al [11] and Ramachandran et al [18]. However, these modifications have their own limitations too.…”