We design and build new precise multifunctional scientific instruments based on cutting-edge measurement techniques and on our interdisciplinary knowledge in physics, material science, micromechanical and electrical engineering, automation, metrology and standardization. This has resulted in variety of purpose-built unique devices, which we are using in our daily lab work. Here are two examples of our recently built scientific instruments: (I) Experimental set-up for direct measurement of magnetocaloric effect, where we can measure simultaneously the adiabatic temperature change and adiabatic magnetostriction; (II) Extension of VSM magnetometry for PPMS system, allowing us to carry out simultaneous measurements of magnetization, magnetostriction, resistivity and sample temperature in near-isothermal conditions.

Direct measurements of the adiabatic temperature change ΔTad and both longitudinal and transversal adiabatic magnetostrictions: The magnetic field is produced by a permanent-magnet set-up (Halbach type, AMT&C) which consists of two cylinders rotating in opposite directions. The magnetic field changes in the bore center from 1.93 T to -1.93 T at a rate of about 1 T/s, fast enough to ignore the heat losses from the sample to the environment during the measurement. The temperature change of the sample is measured using a copper-constantan thermocouple (T-type) with accuracy better than ±0.01 K. Four strain gauges are used for measurements of magnetostriction. Two strain gauges are used for measurements of longitudinal and transversal magnetostriction and two more (glued on sapphire plate) are needed for subtracting the effects of field and temperature on the strain gauge resistivity. For better accuracy the strain gauges are connected to a Wheatstone bridges. The voltage-fed Wheatstone bridges are automatically compensated before each measurement.


Simultaneous measurements of magnetization, magnetostriction, resistivity and temperature change: This scientific instrument greatly enhances the measurement capacity of commercial VSM option of QD PPMS (Fig 2). Two strain gauges are glued on the sample surface for measurements of longitudinal and transversal magnetostriction. Two additional strain gauges are glued on sapphire plate and placed near the sample for correction the changes in strain gauges resistivity induced by external magnetic field and temperature. For measurement of the sample temperature, resistive temperature sensor is welded to the sample by Indium. The resistivity of the sample is measured by using 4-wires technique.

[1] J. Liu, T. Gottschall, K. P. Skokov, J. D. Moore, O. Gutfleisch, Giant magnetocaloric effect driven by structural transitions, Nat. Mater., 11 (7), 620–626, (2012),
DOI: 10.1038/nmat3334.

[2] K. P. Skokov, K. H. Müller, J. D. Moore, J. Liu, A. Y. Karpenkov, M. Krautz, O. Gutfleisch, Influence of thermal hysteresis and field cycling on the magnetocaloric effect in LaFe11.6Si1.4, J. Alloys Compd., 552, 310–317, (2013),
DOI: 10.1016/j.jallcom.2012.10.008

[3] D. Y. Karpenkov, A. Y. Karpenkov, K. P. Skokov, I. A. Radulov, M. Zheleznyi, T. Faske, O. Gutfleisch, Pressure Dependence of Magnetic Properties in La(Fe,Si)13: Multistimulus Responsiveness of Caloric Effects by Modeling and Experiment, Phys. Rev. Appl., 13 (1), 034014, (2020),
DOI: 10.1103/PhysRevApplied.13.034014

Fig 1. Direct measurements of the adiabatic temperature change ΔTad and both longitudinal and transversal adiabatic magnetostrictions. [1-2]; Fig 2. Simultaneous measurements of magnetization, magnetostriction, resistivity and temperature change. (a) Measurement insert and (b) quartz sample paddle with sample and sensors mounted, and (c) transport cap with electrical wiring [3]
Fig 1. Direct measurements of the adiabatic temperature change ΔTad and both longitudinal and transversal adiabatic magnetostrictions. [1-2]; Fig 2. Simultaneous measurements of magnetization, magnetostriction, resistivity and temperature change. (a) Measurement insert and (b) quartz sample paddle with sample and sensors mounted, and (c) transport cap with electrical wiring [3]
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