TITLE

Highly sensitive parylene membrane-based ac-calorimeter for small mass magnetic samples

AUTHOR(S)
Lopeandia, A. F.; André, E.; Garden, J.-L.; Givord, D.; Bourgeois, O.
PUB. DATE
May 2010
SOURCE
Review of Scientific Instruments;May2010, Vol. 81 Issue 5, p053901
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report the microfabrication and operation of a highly sensitive ac-calorimeter designed to characterize small mass magnetic systems operating at very low frequencies (from 0.1 to 5 Hz) in a temperature range from 20 to 300 K. The calorimetric cell is built in the center of a 500 nm thick polymeric membrane of parylene C held up by a Cu frame. On both sides of the membrane defining a three layer structure, electrical leads, heater, and thermometer are deposited as thin film layers of NbNx, with different nitrogen contents, taking benefit of the poor thermal conductance of niobium nitride to thermally isolate the system. This suspended structure ensures very low heat capacity addenda with values in the μJ/K over the 1 mm2 area of the measurement cell. The structuring of the membrane along with suspending of the sensing part only by the parylene bridges leads to a highly reduced thermal link. The calorimeter has been characterized as a function of frequency, temperature, and magnetic field. The thermal link measured is really small reaching values well below 10-8 W/K at 50 K. With these characteristics the frequency of adiabaticity is typically around few hertz and energy exchanges as small as 1 pJ can be detected. Measurements have been performed on Co/Au thin films and on the GdAl2 microcrystal where the ferromagnetic phase transition is clearly evidenced.
ACCESSION #
51059077

 

Related Articles

  • Disorder Tuned Superconductor Insulator Transition in La2− x(Sr/Ce) xCuO4 & NbN Superconducting Thin Films. Vanacken, J.; Zhang, G.; Wambecq, T.; Moshchalkov, V. V.; Leridon, B.; Jin, K.; Zhao, B. R.; Zhu, B. Y.; Raychaudhuri, P.; Chockalingam, S. P.; Chand, M.; Jesudasan, J. // Journal of Superconductivity & Novel Magnetism;Jul2010, Vol. 23 Issue 5, p807 

    In studying the magneto-resistivity ρ( B) in high pulsed magnetic fields up to 55 T, it is often observed that the ρ( B) curves for different temperatures in the vicinity of the critical temperature cross at the same field value, B= B CP. We show how the crossing field changes as a...

  • Another Thin-Film Limit of Micromagnetics. Kohn, Robert V.; Slastikov, Valeriy V. // Archive for Rational Mechanics & Analysis;Nov2005, Vol. 178 Issue 2, p227 

    We consider the variational problem of micromagnetics for soft, relatively small thin films with no applied magnetic field. In terms of the film thickness t, the diameter l and the magnetic exchange length w, we study the asymptotic behavior in the small-aspect-ratio limit t/ l→0, when...

  • Giant magnetoelectric coefficients in (Fe90Co10)78Si12B10-AlN thin film composites. Greve, Henry; Woltermann, Eric; Quenzer, Hans-Joachim; Wagner, Bernhard; Quandt, Eckhard // Applied Physics Letters;5/3/2010, Vol. 96 Issue 18, p182501 

    Thin film magnetoelectric (ME) two–two composites consisting of AlN and amorphous (Fe90Co10)78Si12B10 layers were fabricated by magnetron sputtering on Si (100) substrates. Upon magnetic field annealing they show an extremely high ME coefficient of 737 V/cm Oe at mechanical resonance at...

  • Fabrication condition effects on the magnetic and magnetostrictive properties of sputtered Tb-Fe thin films. Na, S. M.; Suh, S. J.; Lim, S. H. // Journal of Applied Physics;5/15/2003, Vol. 93 Issue 10, p8507 

    Magnetic and magnetostrictive properties of amorphous Tb-Fe thin films are investigated as functions of sputtering conditions such as the substrate thickness, input power, sputtering time, and coverage area ratio of coated thin film to substrate. The observed magnetic and magnetostrictive...

  • Electric-field-induced insulator–metal transition in Pr[sub 0.5]Ca[sub 0.5]MnO[sub 3] thin films in ramp-type junctions. Murakami, T.; SakaI, J.; Imai, S. // Journal of Applied Physics;11/15/2003, Vol. 94 Issue 10, p6549 

    A large decrease in the electrical resistance of the junction was observed with an applied voltage of several volts in small area ramp-type junctions, YBa[sub 2]Cu[sub 3]O[sub 7-δ]/Pr[sub 0.5]Ca[sub 0.5]MnO[sub 3-z]/SrRuO[sub 3]. The lowest resistivity of the Pr[sub 0.5]Ca[sub 0.5]MnO[sub...

  • Exchange biasing of ferromagnetic Cr-doped GaN using a MnO overlayer. Liu, H. X.; Wu, Stephen Y.; Singh, R. K.; Newman, N. // Journal of Applied Physics;8/15/2005, Vol. 98 Issue 4, p046106 

    We report the observation of an exchange biasing of ferromagnetic Cr-doped GaN films by an antiferromagnetic MnO overlayer. The center of the magnetic hysteresis loop shifts to a negative magnetic field by ∼70 Oe when measured after a positive field cooling. An enhancement of the coercive...

  • Discrete deposition as a powerful tool to govern magnetoresistance of the doped manganite films. Tovstolytkin, A. I.; Pogorily, A. N.; Matviyenko, A. I.; Vovk, A. Ya.; Wang, Zh. // Journal of Applied Physics;8/15/2005, Vol. 98 Issue 4, p043902 

    A peculiar preparation routine, namely, a discrete deposition, is proposed for a goal-oriented change of electric and magnetotransport properties of the doped manganite films. The distinguishing feature of such procedure is a division of the whole deposition process into several cycles...

  • Thermoelectric and Magnetothermoelectric Properties of In-doped Nano-ZnO Thin Films Prepared by RF Magnetron Sputtering. Fang, L.; Yang, X. F.; Peng, L. P.; Zhou, K.; Wu, F.; Huang, Q. L.; Kong, C. Y. // Journal of Superconductivity & Novel Magnetism;Aug2010, Vol. 23 Issue 6, p889 

    Nano In-doped ZnO (IZO) films were deposited on glass substrates by RF magnetron sputtering from a powder target (2at% In) at different substrate temperatures. The thermoelectric and magnetothermoelectric properties of the IZO films were investigated. It shows that the prepared IZO films are...

  • Wavy ferromagnetic device as single cell detection. Hao-Ting Huang; Tzong-Rong Ger; Ya-Hui Lin; Zung-Hang Wei // Journal of Applied Physics;2014, Vol. 115 Issue 17, p17E518-1 

    We demonstrate a design of using a wavy permalloy thin film as a cell sensing device for the purpose of single magnetic cell detection. The magnetoresistance curve (MR curve) differs according to the single magnetic cell attached to the surface. By analyzing the MR curves, we can determine the...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics