Category
- Material Characterization » Electrical Characterisation
- Material Characterization » Mechanical Characterisation
- Material Characterization » Magnetic Characterisation
Booking Details
Two types of measurements are possible:
- M vs H: Field is varied at a fixed temperature and magnetization is measured
- M vs T: Temperature is varied at a fixed field
Facility Management Team and Location
suresh@phy.iitb.ac.in
+91-22-25767559
kinikarsr@iitb.ac.in
- Prof. K G Suresh
- Prof. A V Mahajan
- Prof. Maheswaran S.
- Prof. Avradeep Pal
- Prof. Ashwin Tulapurkar
Facility Features, Working Principle and Specifications
Physical property measurement systems are used for the measurement of magnetization of materials. They can measure magnetic moment, magnetization, DC susceptibility, and AC susceptibility of a sample as a function of temperature and/or magnetic field.
- VSM:
- Magnetic field (superconducting magnet): -90 kOe to +90 kOe
- Temperature range (stable or continuous): 1.8 K - 400 K
- Resolution: 10-6 emu
- Sample: bulk/thin film/powder
- SVSM:
- Magnetic field (superconducting magnet): -70 kOe to +70 kOe
- Temperature range (stable or continuous): 1.8 K - 400 K
- Resolution: 10-8 emu
- Sample: bulk/thin film/powder
- AC Susceptibility Measurement: 0.1 Hz to 1 kHz, sensitivity: ≤ 10-8 emu at 0 T.
- Ultra - Low Field Capability: ± 0.05 G with a 7 T magnet.
- VSM Instrument Details (2014):
- Make & Model: Quantum Design, USA
- Installed on: June 2014
- Purchased under the Scheme: RIFC
- VSM Technical Specifications:
- Magnetic Field Range: -90 kOe to +90 kOe
- Temperature Range: 2 K - 325 K
- Resolution: 10-6 emu
- Sample Size (maximum): length ~ 10 mm, breadth ~ 0.5 mm, thickness ~ 0.5 mm
- Sample: bulk/thin film/powder
- SQUID - VSM Instrument Details (2011):
- Make & Model: Quantum Design, USA
- Installed on: October 2011
- Purchased under the Scheme: RIFC
- SQUID - VSM Technical Specifications:
- Operating Range: 1.8 K to 400 K
- Magnetic Field Range: -70 kOe to +70 kOe
- Cooling/Heating Rate: up to 30 K/min
- Resolution: ≤ 8 x 10-8 emu
- Variable Drive Amplitude: 0.1 to 8 mm (peak)
- Sample Chamber I.D.: 9 mm
- Sample Size (maximum): length ~ 10 mm, breadth ~ 0.5 mm, thickness ~ 0.5 mm
- Sample: bulk/thin film/powder
- VSM Instrument Details (2005):
- Make & Model: Quantum Design, USA
- Installed on: September 2005
- Purchased under the Scheme: ISPC - Thrust Area
- VSM Technical Specifications:
- Magnetic Field Range: -90 kOe to +90 kOe
- Temperature Range: 2 K - 325 K
- Resolution: 10-6 emu
- Sample Size (maximum): length ~ 10 mm, breadth ~ 0.5 mm, thickness ~ 0.5 mm
- Sample: bulk/thin film/powder
Instructions for Registration, Sample Preparation, User Instructions, Precautionary Measures and Charges
The operator might call you when loading your sample. Come prepared with the field and temperature sequence required for your measurement. Once the measurements are finished, please enter the number of samples actually measured and take back your samples. We will provide the data in electronic form. On publication of a paper containing these data, please provide the citation to the convener, PPMS central facility.
Register with your LDAP id on the relevant website.
Your sample can be in pellet, powder, or thin film form. In case of a powder sample, enclose it in a sample holder or wrap in Teflon tape. The typical sample mass needed is in the range of 10-50 mg. Submit the sample in a sample bottle/box with sample identification and mass clearly marked. The operator will load the sample for you.
Your sample can be in pellet, powder, or thin film form. In case of a powder sample, enclose it in a sample holder or wrap in Teflon tape.It will be necessary to enclose the sample in something so that it does not fall in the sample chamber. It might be worth measuring the empty sample holder and then subtract this contribution from the sample + holder data. The typical sample mass needed is in the range of 10-50 mg. Submit the sample in a sample bottle/box with sample identification and mass clearly marked. The operator will load the sample for you.
There are several machines available with different field and temperature ranges. PPMS-VSM, SVSM, MPMS extraction magnetometer. Please see the machine specs on the central facility (PPMS) website or discuss with the operator.
Adsorbed oxygen can give a peak of susceptibility at 50K. To be sure, it would be better to flush the sample space above room temperature and re-measure.
Applications
- PPMS-VSM Facility:
- Magnetic moment/Magnetization/dc susceptibility of a sample can be measured as a function of temperature or magnetic field.
- SQUID VSM Facility:
- Magnetic moment/Magnetization/dc susceptibility/AC Susceptibility of a sample can be measured as a function of temperature and/or magnetic field.
Working Principle
- PPMS-VSM Facility:
When a magnetic sample is kept in a uniform magnetic field, a magnetic moment is induced according to the nature of magnetism in the sample. If the sample is now vibrated with a certain AC frequency and amplitude, the moments will induce a signal in a set of pick-up coils kept close to the sample. The signal produced in the coils is proportional to the moment of the sample. If this signal can be calibrated with a known moment, then the moment of the given sample can be obtained. For more details, check www.qdusa.org. - SQUID VSM Facility:
SQUID VSM uses the same working principle as the normal VSM, but the detection coils (ordinary copper coils in VSM) are replaced by a set of SQUID (Superconducting Quantum Interference Device) sensors in the gradiometer assembly. The presence of SQUID sensors ensures that the sensitivity of detection increases. In addition, some extra features like faster cooling/heating rate and faster charging/discharging of the magnet make this instrument faster than the conventional PPMS-VSM. This instrument also has an additional facility to measure the AC susceptibility of the samples. For more details, check www.qdusa.org.