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The thermal stability of Co60Fe20B20 and Co40Fe40B20 thin films are investigated by non-isothermal and isothermal thermal analysis. The differential scanning calorimetry results of amorphous Co60Fe20B20 and Co40Fe40B20 thin films showed the crucial glass forming ability index, γ and γm. The Kissinger formula was applied to calculate the activation energy (Q) of crystallization to measure its resistance of crystallization; 3000 A was a critical thickness. Based on the non-isothermal and isothermal thermal analysis, it reveals that the thermal stability and incubation time of Co60Fe20B20 films are better than Co40Fe40B20 films.

Single crystals of Sr2HoRu1−xCuxO6 (with x=0–0.2), measuring 2–3mm across have been grown from PbO–PbF2 based solutions in the temperature range of 1250–1150°C. The crystals exhibit octahedral morphology and belong to the monoclinic space group P21∕n. While Sr2HoRuO6 is found to be antiferromagnetic with weak ferromagnetism below 30K, the solid solutions containing Cu exhibit a diamagnetic transition at 31K which increases in magnitude and temperature with increasing Cu. Through a correlation of magnetic and calorimetric properties, these crystals are concluded to be spin-glass superconductors.

The authors have fabricated a series of Co∕AlOx(d0)∕Co∕IrMn magnetic tunnel junctions (MTJs), with d0=12–30A. They can be used as ultrasensitive strain gauges. From the resistance (R) versus strain (Δe) curve, the authors find that the maximum value of the gauge factor (γmax) is as large as 5000–20000 in the low-strain (∣Δe∣⩽25×10−6) range. Furthermore, the response is linear. Two mechanisms are proposed to explain the piezoresistance behavior of these MTJs: one is due to the tunneling magnetoresistance effect (the magnetic origin) and the other due to the ordinary tunneling effect (the nonmagnetic origin).

Saturation magnetostriction (λs) of CoFeB∕AlOx∕Co magnetic tunnel junctions (MTJs) has been measured. There are three kinds of MTJs in this study, i.e., glass∕CoFeB(tA)∕AlOx(δto)∕Co(tB) with tA+tB=150A; tA=100, 75, and 50A; and δto=0–30A. When plotting λs as a function of δto, the curve is concave up. We also investigated the compositional distribution of Fe, Al, and O across the tunneling part of the CoFeB(75A)∕AlOx∕Co(75A) junction. Based on these results, we propose a model to describe how the total λs is affected by the CoFeB∕AlOx and AlOx∕Co interfaces.