The current–voltage measurements under flat-top pulsed magnetic fields for non-ohmic transport study

Abstract

Investigation of the non-ohmic transport behaviors under high magnetic fields can provide a new way to explore novel field-induced phenomena. We present the current–voltage measurements under high magnetic fields based on the flat-top pulsed magnetic field system. Two different measurement strategies were compared, given that the excitation current swept continuously or increased by a series of pulses. For the short duration of the flat-top pulsed field, the continuous current method was adopted and well optimized to reduce the Joule heating and achieve the quasi-static measurements. Finally, the non-ohmic behaviors of a quasi-one-dimensional charge density wave Li0.9Mo6O17 were successfully studied under the magnetic field up to 30 T at 4.2 K, which was the first current–voltage measurements carried out in pulsed magnetic fields.

Realisation of the reconfigurable pulsed high magnetic field facility and its scientific application at Wuhan National Pulsed High Magnetic Field Centre

“…Benefited from the CFMS, first I ‐ V measurements under a pulsed high magnetic field have been finished at WHMFC. Figure 14 show the I ‐ V measurements of the quasi‐one‐dimensional CDW sample Li 0.9 Mo 6 O 17 under the flat‐top pulsed field and the change of I ‐ V characteristics with the increase of the magnetic field strength [32].…”

“…Because of the characteristics of high field strength and quasicontinuous duration, the flat-top magnetic field is an ideal platform for performing scientific research, such as specific-heat [16], nuclear magnetic resonance (NMR) [29,30] and currentvoltage (I-V) measurements [31,32] in a pulsed magnetic field.…”

Simultaneous measurement of specific heat and thermal conductivity in pulsed magnetic fields

“…The field stabilization was performed by a proportional-integral-derivative (PID) feedback controller. 20 The feedback-controlled flat-top pulse has enabled us to measure a variety of physical quantities under high magnetic fields such as specific heat, 21,25,26 nuclear magnetic resonance (NMR), 22,24 current-voltage characteristic, 23 etc. The field feedback system consists of the main magnet and the auxiliary homemade mini magnet which compensates for the time dependence of the magnetic field originating from the main magnet.…”

“…This work was followed by various important technique advances 18,19 and the adoption of different measurement approaches with the feedbackcontrolled field stabilization technique for widening the mea-surable conditions. [20][21][22][23][24] On the other hand, measurements of thermal conductivity in pulsed magnetic fields have yet to be demonstrated. With the recent improvement of the field stabilization technique that fully removes the risk of the temperature instability induced by the coupling between magnetic fields and sample temperature, 25,26 it likely becomes possible to measure thermal conductivity under pulsed magnetic fields.…”