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Nanowires are fabricated by template directed electrodeposition with multi-segmented nanowires with combined functionality. Five-segmented nanowires are developed in the sequence of: magnetic material, gold, sacrificial layer, gold, and magnetic material, to be used to create a nanogap electrode pair. The magnetic material was fabricated via pulsed electrodeposition of an alloy containing FeCoNi, the gold was deposited onto the FeCoNi, the sacrificial layer was Cu, and this layer was electrochemically etched in a citrate electrolyte that does not attack the other layers, particularly FeCoNi.

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Alzheimer’s disease (AD) is a neurodegenerative disease, which affects millions of people worldwide. Curing this disease has not gained much success so far. Exhaled breath gas analysis offers an inexpensive, noninvasive, and immediate method for detecting a large number of diseases, including AD. In this paper, a new method is proposed to detect butylated hydroxytoluene (BHT) in the air, which is one of the chemicals found in the breath print of AD patients. A three-layer sensor was formed through deposition of a thin layer of graphene onto a glassy carbon substrate. Selective binding of the analyte was facilitated by electrochemically initiated polymerization of a solution containing the desired target molecule. Subsequent polymerization and removal of the analyte yielded a layer of polypyrrole, a conductive polymer, on top of the sensor containing molecularly imprinted cavities selective for the target molecule. Two sets of sensors have been developed. First, the graphene sensor has been fabricated with a layer of reduced graphene oxide (RGO) and tested over 5–100 part per million (ppm). For the second batch, Prussian blue was added to graphene before polymerization, mainly for enhancing the electrochemical properties. The sensor was tested over 0.02-1 parts per billion (ppb) level of concentration while the sensor resistance has been monitored.

A combination of electromagnetic alignment and topological pattern assisted alignment to position magnetic nanowires, which is referred to as the Patterned Electromagnetic Alignment (PEA), is developed and examined. Electrodeposited, FeNiCo nanowires with different lengths were used as the test nanomaterial, and the microscale grooved surface was formed by UV nanoimprint lithography. The accuracy of the PEA with FeNiCo nanowires was evaluated by measuring the deviation angle from the direction of the magnetic field line for different magnetic field strengths and nanowire lengths, and a statistical alignment distribution was reported for different nanowire length groups. The results were compared with those of the electromagnetic alignment on flat surfaces and in grooved-patterned substrates without electromagnetic alignment. Overall, the deviation angle for the PEA was lower than that for the electromagnetic alignment when all other experimental conditions were identical, indicating that the alignment accuracy along the direction of the magnetic field lines was enhanced in the presence of surface micro grooves. This can be attributed to the fact that, upon attachment of nanowires to the substrate surface, the surface micro grooves in the PEA add additional deterministic characteristics to the otherwise stochastic nature of the nanowire deposition and solvent evaporation processes compared to the sole electromagnetic alignment.

In the past decades, ferromagnet-metalloid alloy films of Co-Fe-B have been widely used in new magnetic devices due to their excellent performance, such as easy industrial-scale fabrication, and considerable ability for tunneling magnetoresistance and perpendicular magnetic anisotropy. However, the insufficient thermal tolerance and interfacial state densities in the typical CoFeB/MgO system limits devices optimization. Because of the improvement in thermal stability and interfacial properties by carbon element replacement, new theoretical and experimental work on Co-Fe-C alloy film properties have been reported. Here, we report on the magnetostrictive behavior, soft magnetism and microwave properties of a series of (Co 0.5 Fe 0.5) x C 1-x films grown on silicon (001) substrates. The addition of carbon changes the Co-Fe-C films from nanocrystalline bcc to an amorphous phase and leads to a high saturated magnetostriction constant of 75 ppm, high piezomagnetic coefficient of 10.3 ppm/Oe, excellent magnetic softness with a low coercivity less than 2 Oe, narrow ferromagnetic resonance linewidth of 25 Oe at X-band, extremely low Gilbert damping of 0.002 and up to 500℃ thermal stability. The large saturated magnetostriction constant and piezomagnetic coefficient result from coexistence of nanocrystalline bcc and amorphous phases. The extremely low Gilbert damping is related to the minimized density of states around Fermi energy of the alloys induced by carbon doping. The combination of these properties makes Co-Fe-C films a promising candidate to be widely used in voltage tunable magnetoelectric devices and microwave magnetic devices.

This work is a part of an on-going research effort to develop an array of micro thermoelectric coolers (TECs) for highly localized control of temperature at the cellular level. Prefabrication experimentation and modeling were carried out to understand the behavior of the proposed device. Mathematical models were used to identify important device parameters and optimal device dimensions. Preliminary experiments have shown that it is feasible to produce the TECs through electrodeposition of bismuth and telluride on modules produced using a modified multistep LIGA (Lithographie, Galvanoformung and Abformung) technique. The development and characterization of the proposed TECs would enable the bioengineer highly localized control of temperature in a native or artificial tissue system. Thus enabling further usage of low temperatures in biological systems for both destructive (cryosurgical) and beneficial (cryopreservation) procedures.