Exchange bias in GeMn nanocolumns: the role of surface oxidation

We report on the exchange biasing of self-assembled ferromagnetic GeMn nanocolumns by GeMn-oxide caps. The x-ray absorption spectroscopy analysis of this surface oxide shows a multiplet fine structure that is typical of the Mn2+ valence state in MnO. A magnetization hysteresis shift |HE|~100 Oe and a coercivity enhancement of about 70 Oe have been obtained upon cooling (300-5 K) in a magnetic field as low as 0.25 T. This exchange bias is attributed to the interface coupling between the ferromagnetic nanocolumns and the antiferromagnetic MnO-like caps. The effect enhancement is achieved by depositing a MnO layer on the GeMn nanocolumns.Comment: 7 pages, 5 figure

Bridging the Divide Between Iterative Optical Polishing and Automation

Several recent business reports have described the global growth in demand for optical and photonic components, paralleled by technical reports on the growing shortage of skilled manufacturing staf to meet this demand. It is remarkable that producing ultraprecision surfaces remains so dependent on people, in contrast to other sectors of the economy, e.g., car manufacturing. Clearly, training can play some role, but ultimately, only process automation can provide the solution. This paper explores why automation is a challenge and summarizes multidisciplinary work aiming to assemble the building blocks required to realize automation

“Supposing that truth is a woman, what then?” The Lie Detector, The Love Machine and the Logic of Fantasy

One of the consequences of the public outcry over the 1929 St Valentine’s Day massacre was the establishment of a Scientific Crime Detection Laboratory at Northwestern University. The photogenic “Lie Detector Man”, Leonarde Keeler, was the Laboratory’s poster boy and his instrument the jewel in the crown of forensic science. The press often depicted Keeler gazing at a female suspect attached to his “sweat box”; a galvanometer electrode in her hand, a sphygmomanometer cuff on her arm and a rubber pneumograph tube strapped across her breasts. Keeler’s fascination with the deceptive charms of the female body was one he shared with his fellow lie detector pioneers, all of whom met their wives – and in William Marston’s case his mistress too – through their engagement with the instrument. Marston employed his own “Love Meter”, as the press dubbed it, to prove that “brunettes react far more violently to amatory stimuli than blondes”. In this paper I draw on the psychoanalytic concepts of fantasy and pleasure to argue that the female body played a pivotal role in establishing the lie detector’s reputation as an infallible and benign mechanical technology of truth

Normal and abnormal body temperature in the elderly

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN024148 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Analysis of the strain distribution in lateral nanostructures for interpreting photoluminescence data

The strain distribution of free standing and buried lateral wire structures based on GaAs [001] containing a In0.14Ga0.86As single quantum well were measured by depth resolved high resolution grazing incidence diffraction in order to interprete photoluminescence PL results obtained from these and similar samples. The spatial strain distribution was analyzed by running strain sensitive in plane scans for different penetration depths below the surface and recording the respective out of plane intensity curves, i.e. truncation rods. The 3D displacement distribution within the wires was derived from the X ray scattering data using a simulation on basis of the distorted wave Born approximation taking into account the adapted parameters of a model structure generated by a finite element calculation. Applying the deformation potential approach the corresponding strain distribution within the quantum well was translated into a local variation of the energy gap. Considering the twofold quantization and the exciton binding energy in addition the variation of the minimum gap energy of the model structures reproduces qualitatively the measured fuctional dependence of the PL shift on the wire widt

Tailoring of magnetic anisotropy in amorphous and nanocrystalline soft magnetic alloys using swift heavy ions

Amorphous films of Fe0.85N0.15 and Fe73.9Cu0.9Nb13.2B8.9 have been prepared by using ion beam sputtering. Magneto optic Kerr effect MOKE and Mössbauer measurements shows that the FeN film has a perpendicular magnetic anisotropy while the finement film has a uniaxial in plane anisotropy. The anisotropy in as deposited state may be attributed to some quenched in stresses present in the film during deposition. Films have been irradiated with Ag and Au ions of different energies. In both the films, irradiation results in gradual removal of anisotropy and a decrease in coercivity, which may be attributed to relaxation of internal stresses. This demonstrates that swift heavy ions can be used for controlled modification of magnetic properties of thin film