In the Magnetic Resonance Laboratory of the Bariloche Atomic Center, different equipment is available for the measurement of magnetic moment as a function of magnetic field, temperature, time, frequency, etc.

  • Vibrating sample magnetometer
  • Kerr effect magnetometer
  • Kerr effect microscope
  • Faraday balance
  • Loop tracer

Contact:
Alejandro Butera
Marcelo Vásquez Mansilla

Vibrating Sample Magnetometer (VSM)
It is a commercial magnetometer of the company Lakeshore model 7300 that senses the magnetic moment of the sample using inductive methods. It features a 7-inch yoke electromagnet and 4-inch and 2-inch pole pieces that allow for maximum magnetic fields of ± 1 or ± 2 Teslas, respectively. In the 4-inch configuration, either a He cryostat or an oven can be attached to cover a measurement range of 4.2 K to 1000 K. The equipment sensitivity is approximately 10 microemu (10-8 A.m2). It has an automated rotator to measure magnetization in different orientations of the sample with respect to the external field. It also has routines for taking remanence measurements (DCD-MRI) and temporal relaxation experiments.
This team provides different services for the analysis of magnetic materials to Universities, Companies and SMEs.

Kerr effect magnetometer
It is a magnetometer that measures the rotation of the polarization axis of light to visualize changes in magnetization. It is a superficial technique (10-20 nm) and relatively fast compared to others.
This magnetometer has been recently built and is still under development. It has an electromagnet with 2-inch pole pieces that currently allow maximum magnetic fields of ± 2000 Oe. We fully expect to have facilities to perform angular variations, measurements depending on temperature and magnetic fields up to 1.5 T.

Kerr effect microscope
This Polar Kerr Effect Magneto-Optical Microscope (PMOKE) allows to visualize the structure of magnetic domains in thin films where the magnetization is out of plane. It allows us not only to study the static structure of magnetic domains, but also to stimulate the system with a magnetic field or electric current and observe its response. Thanks to the modular characteristic of this microscope it is possible to adapt it to different working conditions. Although it is currently mounted on an optical bench in the Polar condition to work at room temperature, it could be changed to a longitudinal configuration, with field and / or current at room temperature or low temperature.

Contact:
Javier E. Gómez
Javier Curiale

Contact:
Alejandro Butera
Marcelo Vásquez Mansilla

Faraday Balance
This magnetometer has been developed and built locally. It is based on the imbalance that occurs in a microbalance due to the force felt by magnetic materials when a controlled magnetic field gradient is applied to them. It features a 10-inch Bruker electromagnet that allows for maximum magnetic fields of ± 1.25 Tesla. The microbalance is from Cahn model 1000. A hot air flow oven is attached to cover a measurement range from room temperature to over 1100 K. The equipment sensitivity is approximately 50 microemu (5×10-8A.m2). It is possible to work in different gas atmospheres (inert, oxidizing, reducing), which allows studying the evolution of magnetic properties along with compositional changes.

Loop Tracer
This alternating field magnetometer has been developed and built locally. It is used for the acquisition of hysteresis loops (AC loop tracer) of magnetic samples with reduced magnetization. The heart of this equipment is an alternating magnetic field generator with a fixed operating frequency of 90 kHz and a maximum field of 200 Oe of peak value. Detection is based on an inductive system of opposing coils and allows a sensitivity of 10-4 emu. The equipment can also be adapted for the calorimetric study of magnetic samples in liquid suspensions.

Contact:
Marcelo Vásquez Mansilla