Twisting Stress-Impedance Effect in Negative Magnetostrictive Amorphous Wire.

Twisting and bending stress in DNA minicircles.

The interplay between bending of the molecule axis and appearance of disruptions in circular DNA molecules, with ∼100 base pairs, is addressed. Three minicircles with different radii and almost equal contents of AT and GC pairs are investigated. The DNA sequences are modeled by a mesoscopic Hamiltonian which describes the essential interactions in the helix at the level of the base pair and inc...

A Magnetic Sensor with Amorphous Wire

Using a FeCoSiB amorphous wire and a coil wrapped around it, we have developed a sensitive magnetic sensor. When a 5 mm long amorphous wire with the diameter of 0.1 mm was used, the magnetic field noise spectrum of the sensor was about 30 pT/ÖHz above 30 Hz. To show the sensitivity and the spatial resolution, the magnetic field of a thousand Japanese yen was scanned with the magnetic sensor.

Noise thermal impedance of a diffusive wire.

The current noise density S2 of a conductor in equilibrium, the Johnson noise, is determined by its temperature T: S2 = 4k(B)TG, with G the conductance. The sample's noise temperature T(N) = S2/(4k(B)G) generalizes T for a system out of equilibrium. We introduce the "noise thermal impedance" of a sample as the ratio deltaT(N)omega/deltaP(J)omega of the amplitude deltaT(N)omega of the oscillatio...

Continuous-wave parametric conversion in hydrogenated amorphous photonic wire

We exploit the high χ nonlinearity present in hydrogenated amorphous silicon nanophotonic waveguides to demonstrate frequency conversion at telecommunication wavelengths using pump and signal that are both continuous-wave. We reach a frequency conversion efficiency close to -34dB having a on-chip 13mW pump power in a low-loss 1cm long silicon photonic wire. Thanks to the ultra-low pump power an...

Direct measurements of magnetostrictive process in amorphous wires using scanning tunneling microscopy