1. Fundamentals of Magnetism and Magnetic Measurements

2. Quantum Design QD has only 2 primary product lines
Magnetic Property Measurement System (MPMS)
Physical Property Measurement System (PPMS)
Over 21 years developing an expertise in automated superconducting magnetometers and integrated measurement systems
QD is highly respected for its system reliability and service
Most systems are used 24 hrs/day, 7 days/week, 365 day/year for many years
QD is the recognized leader in automated, high sensitivity magnetic and electrical property measurement systems
669 MPMS and 311 PPMS systems have been installed in leading research centers throughout the world

3. Quantum Design Magnetic Property Measurement System (MPMS XL™)
The Standard for High-Sensitivity Magnetometry

4. MPMS XL System

5. MPMS XL EverCool™ System

6. MPMS XL Overview
The MPMS XL offers advanced performance in all areas of magnetometry.
Latest design and proven capabilities take SQUID magnetometry to a new level of research
Available in 1, 5 and 7 tesla high homogeneity configurations

7. MPMS XL Benefits Improved measurement sensitivity
Increased measurement speed
Enhanced temperature control
MPMS MultiVu™ WindowsXP Operating System

8. MPMS XL Temperature Control
Patented dual impedance design allows continuous operation below 4.2 K
Sample tube thermometry improves temperature accuracy and control
Transition through 4.2 K requires no He reservoir refilling and recycling (no pot fills)
Temperature sweep mode allows measurements while sweeping temperature at user controlled rate
Increases measurement speed
Smooth temperature transitions through 4.2 K both cooling and warming

9. MPMS XL Temperature Control

10. MPMS XL Temperature Control

11. MPMS XL Temperature Control
Temperature Range: K (800 K with optional oven)
Operation Below 4.2 K: Continuous
Temperature Stability: ±0.5%
Sweep Rate Range: K/min with smooth transitions through 4.2 K
Temperature Calibration ±0.5% typical Accuracy:
Number of Thermometers: 2 (one at bottom of sample tube; one at the location of sample measurements)

12. Magnetic Field Control
Very high homogeneity magnets (1, 5 and 7 Tesla)
0.01% uniformity over 4 cm
Magnets can be operated in persistent or driven mode
Hysteresis mode allows faster hysteresis loop measurements
Magnets have two operating resolutions: standard and high resolution

13. Hysteresis Measurement

14. Reciprocating Sample Measurement System (RSO)
Improved measurement sensitivity
Increased measurement speed
No waiting for the SQUID to stabilize
Very fast hysteresis loops up to 8x faster than conventional MPMS
Servo motor powered sample transport allows precision oscillating sample motion
High precision data acquisition electronics includes a digital signal processor (DSP)
SQUID signal phase locked to sample motion
Improved signal-to-noise ration
Low thermal expansion sample rods with sample centering feature

15. Reciprocating Sample Measurement System (RSO)

16. RSO Data The DC scan took 56 hours to take 960 points
The RSO scan took 1600 points in under 24 hours!
The RSO scan avoids subjecting the sample to field inhomogeneities that effected the DC scan.

17. RSO Data
The system stayed below 4.2 K for 30 hours to acquire a measurement every 100 Oe up to and down from 5 tesla
By moving the sample only 0.5 mm using RSO, the sample was exposed to very little field inhomogeneity.

18. RSO Data
The system stayed below 4.2 K for 33 hours to perform these hysteresis measurements in a single sequence
There are 3350 data points in this graph

19. Hysteresis Mode Data
This measurement takes ~ 3.5 hours in persistent mode

20. Reciprocating Sample Measurement System (RSO)
Frequency Range: Hz
Oscillation Amplitude: mm
Relative Sensitivity: < 1 x 10-8 emu; H  2,500 Oe, T = 100 K (for 7-tesla magnet)
 6 x 10-7 emu; 7 tesla, T = 100 K (for 7-tesla magnet)
Dynamic range 10-8 to 5 emu (300 emu with Extended Dynamic Range option)

21. MPMS MultiVu Control Software
MS WindowsXP-based - pull down menus and mouse control
Simultaneous access to all aspects of system operation
Multiple documents and views visible and useable at the same time
Simultaneous display of data files in multiple formats
Simplified, more powerful, measurement sequence editor
Automatic Background Subtraction routine

22. MPMS MultiVu Control Software

23. MPMS System Options Transverse Moment Detection
for examining anisotropic effects
Second SQUID detection system
SQUID AC Susceptibility
2 x 10-8 emu sensitivity 0.1 Hz to kHz
Ultra-Low Field
Reduce remanent magnet field to < 0.05 Oe
Extended Dynamic Range
Measure moments to ±300 emu
External Device Control
Control user instruments with the MPMS
Sample Rotators
Vertical and Horizontal
Sample Space Oven
Temperatures to 800 K
Environmental Magnetic Shields
Fiber Optic Sample Holder
Allows sample excitation with light
Manual Insertion Utility Probe
Perform elector-transport measurements in MPMS
Liquid Nitrogen Shielded Dewar
EverCool Cryocooled Dewar
No-Loss liquid helium dewar
No helium transfers

24. Transverse Moment Detection
Measures anisotropic effects of moments with vector components perpendicular to the applied field
Incorporates a second SQUID detection system which can resolve transverse moments as small as 10-6 emu
Second-order detection coils orthogonal to the longitudinal detection coils

25. SQUID AC Susceptibility
Dynamic measurement of sample
Looks also at the resistance and conductance
Can be more sensitive the DC measurement
Measures Real () and Imaginary () components
 is the resistance of the sample
 is the conductive part
Proportional to the energy dissipation in the sample
Must resolve components of sample moment that is out of phase with the applied AC field
SQUID is the best for this because it offers a signal response that is virtually flat from 0.01 Hz to 1 kHz
Available on all MPMS XL systems
Requires system to be returned to factory for upgrade

26. SQUID AC Susceptibility
Features
Programmable Waveform Synthesizer and high-speed Analog-to-Digital converter
AC susceptibility measured automatically and can be done in combination with the DC measurement
Determination of both real and imaginary components of the sample’s susceptibility
Frequency independent sensitivity
Specifications
Sensitivity (0.1 Hz to 1 kHz): 2 x Tesla
1 x Tesla
AC Frequency Range: 0.01 Hz to 1 kHz
AC Field Range: to 5 Oe (system dependent)
DC Applied Field: to 70 kOe (system dependent)

27. SQUID AC Susceptibility

28. Ultra-Low Field Capability
Actively cancels remanent field in all MPMS superconducting magnets
Sample space fields as low as Oe achievable
Custom-designed fluxgate magnetometer supplied
Includes Magnet Reset
Requires the Environmental Magnet Shield

29. Hysteresis measurement

30. Extended Dynamic Range
Extends the maximum measurable moment from ± 5 emu to ± 300 emu (10 orders of magnitude)
Automatically selected when needed in measurement
Effective on both longitudinal and transverse SQUID systems

31. Sample Space Oven Provides high temperature measurement capability
Ambient to 800 K
Easily installed and removed by the user when needed
A minimal increase in helium usage
Approximately 0.1 liters liquid helium/hour
3.5 mm diameter sample space

32. MPMS Horizontal Rotator
Automatically rotates sample about a horizontal axis during magnetic measurement
360 degrees of rotation; 0.1 degree steps
Sample platform is 1.6 X 5.8
Diamagnetic background signal of 10-3 emu at 5 tesla

33. Manual Insertion Utility Probe
Perform electro-transport measurement in the MPMS sample space
10-pin connector
Use with External Device Control (EDC) for controlling external devices (e.g., voltmeter and current source)
Creates fully automated electro-transport measurement system

34. External Device Control
Allows control and data read back from third party electronics
Allows custom control of MPMS electronics
Use with Manual Insertion Utility Probe for automated electro-transport measurements
MPMS MultiVu version written in Borland’s Delphi (Visual Pascal) programming language

35. Hysteresis Measurement made with External Device Control (EDC)
Using EDC to control a DC field using the AC coil in the MPMS
Up to ± 8 Oe DC field (system dependent)
Step size as small as 1.9 Oe
20 Å Ni Thin Film (PSI, Zurich)

36. Fiber Optic Sample Holder
Allows sample to be illuminated by an external light source while making magnetic measurements
Optimized for near UV spectrum (180 to 700 nm)
Includes 2-meter fiber optic bundle
Sample bucket 1.6 mm diameter and 1.6 mm deep
Slide seal
Fiber optic bundle
SMA connector

37. MPMS Liquid Helium Dewar Options
Basic system supplied with a vapor shielded 56 liter dewar
Liquid nitrogen jacketed version of the basic dewar improves hold time by ~ 30%
MPMS EverCool Cryocooled Dewar

38. MPMS EverCool Dewar
Designed to eliminate the need for liquid helium transfers
Virtually eliminates all helium loss from the Quantum Design MPMS magnetometer system
Cryocooler-dewar system that recondenses the helium directly in the dewar
Integrated into MPMS Operating System
Cryocooler operation can be controlled automatically to minimize interference with sensitive magnetic measurements
Available as an upgrade to all MPMS systems (no equipment needs to be returned to Quantum Design)
Available with water or air cooled compressor

39. MPMS EverCool Dewar
Cryocooler
coldhead
Liquid helium
condenser unit

40. MPMS EverCool Dewar

41. MPMS MultiVu™ Control Software
MPMS MultiVu Windows-based control software takes full advantage of MicroSoft’s Multi Document Interface (MDI)
User friendly environment using common Windows protocols
All system and measurement operations controlled using pull-down menus
Provides the ability to observe multiple data graphs to compare old data with data begin acquired
Each user can set their own measurement sequences and data files so experimental set-ups and data are safe on the multi-user system
Remote operation of the system and remote service capability with MPMS computer connected to Internet
WindowsXP version available End of 2002

42. MPMS MultiVu Control Software

43. MPMS MultiVu Control Software

44. System Installation and Acceptance
Every MPMS sale includes complete system installation and customer training
Up to 5 days
During the installation, the system will be tested to meet a set number of specifications

45. Currently in Development: High Pressure Cell
Manufactured by easyLab Limited in the UK
Offers 10 kbar of pressure
Supplied with complete user’s kit

46. Quantum Design MPMS
Designed For Scientists, By Scientists

47. A Brief History of Superconductivity

48. The Chronology
1911 – Heike Kammerlingh Onnes discovers superconductivity
1913 Receives the Nobel Prize in Physics
1962 – Brian Josephson predicts the “Josephson Effect”
1973 Receives the Nobel Prize in Physics
1986 – Bednorz and Muller discover High Temperature Superconductivity
1987 They receive the Nobel Prize in Physics

49. The SQUID
Within a year of Brian Josephson’s discovery, the first Superconducting Quantum Interference Device (SQUID) was built
In 1968, Professor John Wheatley of UCSD and four other international physicists founded S. H. E. Corp. (Superconducting Helium Electronics) to commercialize this new technology.

50. SQUID Magnetometers
The first SQUID magnetometer was developed by Mike Simmonds, Ph.D. and Ron Sager, Ph.D. while at S.H.E. Corporation in 1976.
In 1982, Mike and Ron, along with two other SHE employees, founded Quantum Design.
In 1984, QD began to market the next generation SQUID magnetometer – the Magnetic Property Measurement System (MPMS).
In 1996, QD introduced the MPMS XL as the latest generation SQUID magnetometer
During the past 18 years, six companies have design and marketed SQUID magnetometers to compete with the MPMS. Of these only one still exists – Cryogenic Limited in the UK.

51. The Superconducting Components
The superconducting magnet
The superconducting detection coil
The Superconducting QUantum Interference Device (SQUID)
The superconducting magnetic shield surrounding the SQUID

52. The SQUID System
The Superconducting QUantum Interference Device (SQUID) give the MPMS is the source of the instrument’s sensitivity
Extremely sensitive current-to-voltage converter
Sample moving through the superconducting detection coils induces a small current in the coils
SQUID output voltage is proportional to the magnet moment of the sample

53. The Detection Coil
The MPMS XL uses a second-order gradiometer configuration
Positioned at the center of the magnetic field
Reduces noise from uniform distance sources
Part of a closed superconducting loop