PPMS Physical Property measurement system Integrated measurement applications

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1 Our most versatile instrument offering the widest range of magnetic, thermal and electrical measurements System features MultiVu software PPMS MultiVu is a powerful software for the performance of complex measurements with a maximum of automatization. It allows both the measurement and evaluation of comprehensive data sets. Complex measurement sequences can be created by simply using click-and-drop. Data can be viewed in a graphic, tabular, or raw data format. The raw data may either be processed directly by MultiVu or exported as an ASCII file to be processed by the user. The Quantum Design Physical Property Measurement System (PPMS) represents a unique concept in laboratory equipment. It is an open architecture, variable temperature-field system that is optimized to perform a variety of automated measurements. At Quantum Design we know your time is valuable, so we brought laboratory automation to a new level. While the PPMS automatically runs your measurements, you can be analyzing data from previous measurements, plaing your next experiment, and creating new materials. The PPMS works like a dedicated system, but its tremendous flexibility lets you perform different types of measurements. Plus, you can easily integrate your own unique experiment with the ppms. The following pages list specially configured PPMS instruments for heat capacity, magnetometry, and electrotransport applications. However, any of the capabilities can be combined to configure a system suitable for your particular research needs. Third party instruments (e.g. external current sources) may easily be controlled via MultiVu. This allows the user to create customized setups without losing the automation of the measurements runs. PPMS sample chamber Outer wall of sample chamber Contact leads Sample Sample puck Keyed buttom coector Ease of use The hallmarks of the PPMS are automation and ease of use. You can quickly and easily configure the PPMS to perform different types of measurements. In a matter of minutes you can install a measurement application, set up an automated sequence, and start collecting meaningful data. And, the PPMS is designed to run 24 hours a day, 7 days a week. Much of the versatility of the PPMS is based on the design of the PPMS probe. The probe incorporates the magnet, the temperature control, and the sample puck coector.

2 Sample mounting The PPMS sample-mounting system is the most interesting and unique feature of this instrument. At the bottom of the sample chamber is a 12-pin coector pre-wired to the system electronics. This coector allows you to plug in a removable sample insert or sample puck and offers convenient access to electrical leads for application hardware and electronics. Most pucks include a thermometer in close proximity to your sample, some of the measurement pucks also include a heater. You can use this puck technology for integration of own experimental ideas. Temperature control operation To control the temperature, a vacuum pump draws helium into the aular region where heaters warm the gas to the correct temperature. This design reduces thermal gradients and increases system flexibility by making the sample chamber a controllable environment. For example, the sealed sample chamber may hold a high vacuum without the need for additional inserts. This is significant for the use of the heat capacity and Helium-3 capabilities. The temperature control system offers the following features: Temperature sweep capability allows measurements to be taken while sweeping the temperature at a user-defined rate ( K/min). Continuous Low-Temperature Control (CLTC) ensures precise temperature control, unlimited operation below 4.2 K, and smooth transitions through the 4.2 K helium boiling point. Temperature range of K accommodates many different types of measurements. Optional capabilities can be used to extend the temperature range. A helium-3 or a dilution refrigerator are available to reach lower temperatures. The VSM option can run up to K with an oven. Specialized pucks, 2.4 cm in diameter, are used for different measurement applications Open architecture The tremendous flexibility of the PPMS lets you create your own experiments and easily interface your own third-party instruments to the PPMS hardware. The PPMS MultiVu software supports linking capabilities, so you can write your own programs in Delphi, C++, or Visual Basic to synchronize PPMS functions with the activity of other instruments to perform your custom experiment. The model 6000 PPMS controller houses and controls all the important components of the instrument to provide direct communication with the application electronics for rapid data acquisition. Configurable thermometry The UserTemp feature makes it extremely easy for you to incorporate your own calibrated thermometer into the hardware so that your thermometer can control the system temperature. UserTemp not only reads the thermometer but also controls the helium gas flow and heaters to minimize the time required to stabilize at each selected temperature. Many of the PPMS options utilize this feature to monitor the temperature close to the sample. Field control The PPMS can be configured with a 9 T, 14 T or 16 T longitudinal magnet or a 7 T transverse magnet. The low noise, bi-polar power supply allows continuous charging through zero field with current compensation and over-voltage protection. The self-contained 3 He Refrigerator lowers the minimum sample temperature to <0.4 K

3 Thermal measurements Quantum Design offers with the heat capacity and the thermal tansport option two powerful thermal measurement options for the PPMS. The measurement of the heat capacity of solids can provide considerable information about the lattice, electronic, and even magnetic properties of materials. In measuring the thermal transport properties of a material specimen a researcher can learn considerable information about the electronic as well as the ionic lattice structure of that specimen. Thermal conductivity is a measure of the ability of a material to conduct heat. Thermal transport option (TTO) The thermal transport option (TTO) enables measurements of thermal properties, including thermal conductivity κ and Seebeck coefficient (thermopower) α. The system measures fully automated the thermal conductivity by monitoring a temperature drop as a known amount of heat passes through the sample. For the thermoelectric Seebeck effect the system measures the voltage drop across the sample as a heat pulse is applied. The temperature drop and the voltage drop are measured simultaneously and in combination with a four-probe resistivity measurement the so-called thermoelectric figure of merit (ZT = S 2 T/(ρκ) ) is received, which is of main interest for the investigation of thermoelectric materials. Specially designed heater and thermometer shoes, which can be used for different sample shapes and which can be used in four-probe or two-probe configuration. Small and highly accurate thermometers feasible for the measurement of small temperature differences Ideal environment due to high vacuum in the sample chamber (TTO requires the high vacuum option) Sophisticated software which uses a dynamical model of the heat flow A continuous measurement while sweeping the temperature is possible as well as doing the measurement at a certain constant temperature Measurement capabilities Temperature range Pressure Thermal conductivity κ Seebeck coefficient S Electrical resistivity ρ Thermoelectric figure of merit ZT K High vacuum (<10-4 torr) Heat capacity To use the heat capacity option, you mount the sample on an easy-toinstall, plug-in microcalorimeter sample puck using a special samplemounting fixture The heat capacity measurement system performs fully automated relaxation heat capacity measurements. Each measurement is analyzed using a sophisticated two-tau model to accurately simulate the effect of the heat flow between the microcalorimeter platform and the sample (tau2) as well as the heat flow between the platform and puck stage (tau1). The heat capacity measurement system includes a high-vacuum system. Advanced heat capacity algorithms calculate the actual thermal coupling of the sample to the microcalorimeter platform, curve fit the data, and then compensate for this coupling when determining the heat capacity of the sample. A built-in data subtraction feature automatically removes the background heat capacity of the sample platform and adhesive. All calculated fitting parameters and raw data, including a χ 2 quality value, are saved in the data file. Application software automatically acquires, analyzes, and displays data. Temperature range Temperature extension Sample size Resolution K with low temperature stages (He-3, DR) mg 10 nj/k at 2 K

4 Magnetometry AC/DC magnetization The magnetometry applications can be embedded in the PPMS with its automated field and temperature control capabilities. The result is a powerful magnetic workstation for different requirements of sample characterization Moment (emu) Servo-motor, coil set, and sample rod for the ACMS VSM The vibrating sample magnetometer (VSM) is a powerful measurement system to be used for magnetic sample characterization. The VSM option transforms your PPMS into a sensitive DC magnetometer for fast data acquisition. The movement of the sample is done by a special sample transport, which has a linear characteristic and thus is very precise and flexible. The optional oven and large bore upgrade are useful and further extend the capability of the VSM Magnetic Field (Oe) Rapid and completely automated centering operation of the sample. Sensitive DC magnetic moment measurement up to the maximum field of the magnet VSM measurement system is based on the CAN network protocol and includes the Model 1000 CAN tower Sweeping of the magnetic field or of the temperature while doing the measurement is possible RMS sensitivity 10-6 emu or 0.5% Typical sample mass <1 g Oscillation amplitude (typical) 0.5 to 3 mm Frequency 40 Hz Coil-set bore 6.3 mm Large bore coil-set (optional) 12 mm bore Sample temperature K Sample temperatures with VSM oven (optional) K sensitivity:10-5 emu The AC measurement system (ACMS) provides you with the capability to perform both AC susceptibility and extraction DC magnetization measurements without changing hardware. A single automated measurement sequence can perform both AC and DC magnetization measurements. Direct measurement of the instrumental phase shift, not available on any other AC susceptometer: This feature uses integrated, low inductance calibration coils to measure and subtract background phase shifts prior to every AC measurement point. High-speed digital filtering: By using a DSP chip, the ACMS improves the signal-to-noise ratio over analog filters to offer excellent performance over a wide frequency range. A compensation coil reduces environmental noise in AC susceptibility measurements. Temperature range AC frequency range AC field amplitude range AC susceptibility sensitivity DC sensitivity K 10 Hz to 10 khz 2 moe to 15 Oe 2 x 10 8 emu at 10 khz 2.5 x 10-5 emu to 5 emu Temperature stability may be reduced at low temperatures due to sample movement.

5 Ultra low field Torque magnetometry* The ultra low field (ULF) for the PPMS, actively cancels residual magnetic flux in the PPMS superconducting magnets so samples can be cooled in a very low field. The PPMS ULF option uses an additional superconducting coil wound directly on a specially designed coil form that fits between the magnet and the PPMS outer vacuum jacket. The field in the sample space is measured using a customdesigned fluxgate magnetometer. An automated routine measures the remanent field in the sample chamber and uses the superconducting nulling coil to cancel the remanent field. It then performs a controlled quench of the primary superconducting magnet to trap this zero flux state so that the power to the nulling coil can be turned off. The process is iterated to achieve extremely low remanent field. The fluxgate also allows low field profiling of the magnetic field in the sample chamber. Residual field Residual field uniformity < 0.1 Oe at any point < ±0.1 Oe along 4 cm at the center of the coil set The ultra low field option is optional also available for the PPMS-VSM magnetometer system. Tq-Mag chip with integrated Wheatstone bridge The PPMS model P550 torque magnetometer option (Tq-Mag) incorporates a torque-lever chip mounted on a PPMS horizontal or vertical rotator platform for performing fully automated, angular-dependent magnetic moment measurements at a wide range of fields and temperatures. Specifically designed for measuring small, anisotropic samples (e.g., single crystals, thin film samples, etc.), this highly sensitive torquemeter utilizes a piezoresistive technique to measure the torsion of the lever created by the applied magnetic field on the sample moment Tq-Mag provides excellent sensitivity in high magnetic fields normally not accessible in other measurement techniques. This torque detection system offers substantial immunity to gravity effects and minimal temperature dependence, which is accounted for in an automated calibration of the torque lever. This option includes: Torque magnetometer chips Special rotator platform sample boards with chip holder Software module that integrates into the PPMS operating system Tq-Mag may be used in both the longitudinal and transverse magnet configurations. The required rotator aids in locating the angle of the sample that gives the largest signal when measuring torque versus field. Sample size Up to 2 x 2 mm 2 RMS Torque noise level 1 x 10-9 Nm for 40 sec. sampling time * Quantum Design developed the torque magnetometer in collaboration with the IBM Research Division, Zürich Research Laboratory, and the physical institute of the University of Zürich, Switzerland.

6 Electro transport The PPMS offers automation and convenient sample mounting for all types of angular-dependent electro-transport measurements, including resistivity, hall effect, I-V curves, and your own experimental design. Let Quantum Design simplify your transport measurements. Electro-transport option (ETO) The electro-transport option (ETO) enables users to make several different types of electric transport measurements over a wide range of resistance values and sample types. It includes the measurement of AC and DC resistance, I-V curves, and differential resistance. DC resistivity The DC resistivity option adds resistance bridge capability to the model 6000 PPMS controller. This bridge provides four independent chaels that you can use for van der Pauw and four-wire resistance measurements (up to three samples in a single sequence). Current range Sensitivity 5 na to 5 ma 20 nv Resistance [Ω] dt/dt = K/min averaging time = 15 sec excitation current =80 µa except: Oe : Oe H = 0 H = 10 Oe H = 30 Oe H = 60 Oe H = 100 Oe H = 120 Oe AC transport measurement system (ACT) The AC transport measurement system (ACT) option is a precision current source and voltage detector that supports four different types of automated, electrical transport measurements: AC resistivity, five-wire Hall effect, I-V curve, and critical current. A PPMS with integrated ACT provides fast data acquisition and the convenience of measuring up to two samples on a single sample mount. Current range Current range: sensitivity Frequency range 10 µa to 2 A 1 1 khz 1 Hz to 1 khz Temperature [K] Electrical transport option on dilution refrigerator: resistance vs. temperature on sample of Ir 1-x Ru x Sample contact in two or four-probe configuration Two different chaels for the simultaneous measurement of two samples Each chael consist of a high precision current source and a voltage preamplifier coupled to a digital signal processor. Can be used as additional option to ACT or as stand-alone Electro-transport option on your PPMS Current range Frequency range Typical resistivity range 10 na to 100 ma in continuous operation DC, and 0.1 Hz to 200 Hz in AC 10 µω to approx. 10 MΩ (4-wire mode) 1 MΩ to 5 GΩ (2-wire high resistance mode)

7 Horizontal and vertical rotators Multi-function probe The multi-function probe option extends measurement capabilities of the PPMS by allowing you to easily add hardware such as fiber optics, microwave guides, and external electrical leads to customize your experiment. This probe incorporates the PPMS sample space electrical coections and can utilize the electro-transport accessories. Pressure cell Horizontal rotator with various sample-mounting platforms. You may take advantage of the horizontal and vertical rotators to obtain information about angular dependence. Samples are mounted on removable platforms. A thermometer, in direct contact with the platform, accurately determines the sample temperature. Both rotators are available with standard or high-resolution motors. Range -10º to 370º The horizontal rotator option rotates the sample about the horizontal axis. Angular step size 0.053º for standard resolution; º for high resolution The vertical rotator option rotates the sample about the vertical axis. Angular step size 0.013º for standard resolution; 0.002º for high resolution Compatible with DC resistivity AC transport option Torque magnetometry option For electric measurements under pressure a PPMS pressure cell is offered. The cell has a sample space of 4.4 cm and it fits into the puck coector. Maximum pressure (load) Maximum sample 7 K 2.0 GPa or 3.0 GPa 1.6 GPa or 2.4 GPa Different sample-mounting structures for the rotators are available for each type of measurement. These platforms hold the sample parallel or perpendicular to the field. Vertical rotator is pictured.

8 Surface physics Let your PPMS host an SPM insert and get new exiting possibilities. You just use the easy way of controlling the magnetic field and the temperature for surface investigation. The PPMS- SPM insert is manufactured by attocube systems and it offers atomic force (AFM), magnetic force (MFM), confocal microscopy (CFM) or scaing hall probe microscopy (SHPM) measurements. At cryogenic temperatures, the combination of high resolution power, clear optical spectra, and reduced thermal noise can be achieved. The plug-and-play experimental setup has made this technique the method of choice for a variety of applications ranging from examining physical structures like semiconductor quantum dots and NEMS/ MEMS devices to the emerging area of nano-optics. High resolution confocal imaging Various detection modes such as reflection, luminescence, fluorescence,... Coupling of the light to other detectors possible, e.g. spectrometer, APD,... Interferometric deflection detection Large range, patented coarse positioning system SPM Suitable for a temperature range from 2 K to 400 K Suitable for magnetic fields up to 16 T Easily interchangeable SPM heads Large cryogenic scan range (12 x 12 μm 2 ) Minimum drift in variable field/temperature. AFM/MFM The PPMS-AFM is the perfect choice if it comes to demanding imaging applications such as high-resolution scaing of topographic or magnetic information of a sample under variable magnetic field or temperature. High resolution AFM and MFM imaging Quick sample and cantilever exchange offers all common contact and non-contact modes contact mode, non-contact mode Imaging modes AFM, EFM, SGM, ct-afm (conducting tip AFM) Measured RMS z-noise 0.05 nm (expected) Contact 4 K, 0.12 nm (guaranteed) 5 ms pixel integration time Excitation wavelength range Light source Detection mode SHPM 400 nm to 1500 nm Fiber coupled laser, typically 635 nm E.g. reflection, luminescence, fluorescence,... The attoshpm xs is an ultra-compact scaing Hall probe microscope, designed particularly for the operation at low temperatures and high magnetic fields. The heart of the SHPM, a molecular beam epitaxy (MBE) grown GaAs/AlGaAs Hall sensor measures magnetic fields with unrevealed sensitivity. Local measurements of the magnetization of a sample are obtained by scaing the sample underneath the Hall sensor and simultaneously recording the Hall voltage, directly yielding the local magnetic field. While other local probes may outperform the Hall sensor with respect to its lateral resolution, its ability to non-invasively obtain quantitative values for the local magnetic field makes the Hall sensor a unique tool for the study of superconductors and other magnetic materials. The exceptional combination of materials allows absolutely stable high resolution imaging of surfaces/local magnetic field Close-up of the MBE grown SHPM chip, showing its Hall-sensor/STM leads and the bond wires for electrical coection to the chip carrier. The Hall sensors are available as high resolution and ultra-high resolution versions, featuring an active Hall area of 500 nm and 300 nm, respectively. CFM Confocal microscopy (CFM) is the method of choice for obtaining clear optical images with high resolution (diffraction limited) and high optical throughput. Operation mode Area field sensitivity Constant height, or dual pass 500 nm (high resolution) 300 nm (ultra high resolution)

9 Low temperature stages To reach temperatures below 1.9 K two optional refrigerator systems are available, a helium-3 and a dilution refrigerator. Both systems have a closecycle gas design and operate fully automated. No need for manually operation of any valve Easy plug-in of the probe in the sample chamber System is completely mounted on a moveable cart Horizontal oriented sample stage helium-3 probe Temperature range Cool-down time from 300 K to 0.5 K Compatible with <0.4 K to 350 K 3 h or less DC resistivity AC transport option Heat capacity option Complete helium-3 system with probe, diaphragm pump, and cart Helium-3 system To reach temperatures below 1.9 K, an optional 3 He refrigerator is available. This probe provides a minimum temperature of less than 0.4 K. A new concept in refrigeration design, this self-contained helium-3 refrigerator operates by continuously circulating 3He in a closed-cycle, sealed system, eliminating the need for low-temperature seals and manual valves. The Helium-3 system provides fully automated control of the pumps to support measurement capability up to 350 K. This option is specifically designed to provide lower temperatures for heat capacity and electrotransport measurements. Cooldown time from 300 K to 0.5 K is less than three hours. Dilution refrigerator The dilution refrigerator system can be used for heat capacity and electro-transport option (ETO). Fully automated operation Easy plug-in of the probe in the sample chamber System is completely mounted on a moveable cart Temperature range Cool-down time from 300 K to 100 mk Cooling power Compatible with 50 mk to 4 K 8 h or less 2 mw at mixing chamber, 0,25 mw at sample chamber Electro transport option Heat capacity option

10 Dewar and liquid helium saving options The PPMS can be configured with different types of cryogenic dewars. From the classic liquid helium dewar with a vacuum shield to close-cycle systems with effective reliquefication technology, which makes the user independent from regular supply of liquid helium. Standard dewar The standard dewar has a hold time of up to 6 days. Helium reliquefier The reliquefier is the perfect add on for a high-capacity nitrogen-jacketed dewar. The vaporized helium is returned to a pulse-tube cooler, which is mounted over the PPMS dewar. After condensing the helium the liquid drips back into the PPMS dewar. As soon as your system is cold, there is no need for a refill of liquid helium. Any helium losses like flushing the sample chamber are compensated from a gas cylinder. Liquid helium capacity Static boil-off with Probe 30 L <5 L/d Liquefaction rate Compressor type 10 L/day water-cooled EverCool-II dewar High-capacity LN 2 -jacketed dewar This dewar upgrade reduce the consumption of liquid helium by approx. 40% and extends the time between a refill of liquid helium. Liquid helium capacity Static boil-off with probe Liquid nitrogen capacity Static boil-off with probe 68 L <3 L/d 48 L <2 L/d The EverCool-II dewar makes your PPMS cryogen-free. You just start from helium gas at room temperature and a high-efficiency cold head is cooling down to 4 K and starts liquiefication. Even it is a cryogenfree system, the dewar still has some liquid helium, which offers the flexibility of turning-off the cold-head for a certain time. Cool-down time Liquefaction rate Compressor type approx. 30 h approx. 8 L/day air-cooled Comparison of reliquefier and EverCool II Reliquefier Few vibrations (No effect on He 3 refrigerator, little effect on SPM) PPMS remains fully functional when the reliquefier is removed (e.g. for maintenance) and has its full Helium capacity Upgrade can be done in situ EverCool II Little space requirements Full automation Capable to cool down from Helium gas only

11 Base system specification Magnet options Longitudinal Transverse ±9 T, ±14 T, ±16 T ±7 T split coil Field uniformity 9 T longitudinal ±0.01% over 5.5 cm x 1 cm diameter cylindrical volume (typ.) 14 T longitudinal ±0.1% over 5.5 cm 16 T longitudinal ±0.1% over 1 cm DSV 7 T transverse ±0.1% over 1 cm DSV Bi-polar power supply 9 T longitudinal 50 A Slew rate 1 19 mt/s (typ.) 14 T longitudinal 100 A Slew rate mt/s (typ.) 16 T longitudinal 120 A Slew rate 1 22 mt/s (typ.) 7 T transverse 50 A Slew rate mt/s. (typ.) Control modes Persistent and driven modes Linear Oscillating No overshoot Resolution 9 T longitudinal 0.02 mt to 1 T 0.2 mt to 9 T 14 T longitudinal 0.03 mt to 1.5 T 0.3 mt to 14 T 16 T longitudinal 0.03 mt to 1.5 T 0.3 mt to 16 T 7 T transverse 0.02 mt to 0.75 T 0.2 mt to 7 T Temperature control Temperature range Accuracy Slew rate Control modes Stability Sample space size K ±1% zero to full field (up to 16 T) K/min. No overshoot fast settle temperature sweep ±0.2% for T <10 K (typ.) ±0.02% for T >10 K (typ.) 2.5 cm diameter UPS requirement Maximum current load 17 A PPMS utility inserts

12 Chart of options Model PPMS-0 PPMS-9 PPMS-14 PPMS-16 PPMS-7- Trans PPMS- DynaCool* Magnet No magnet Longitudinal Longitudinal Longitudinal Transverse Longitudinal Field 9 T 14 T 16 T 7 T split-coil 9 T / 14 T Heat capacity P TTO P ~mid 2014 VSM P VSM oven P VSM-ULF P N N N 4 in future ACMS P N N 4 in future ACMS-ULF P N N N N Torque P in future DC resistivity P ACT P N ETO P Vertical rotator P N Horizontal rotator P MFP P Sample test box P S Pressure cell HPC PPMS-SPM in future Helium-3 P ~spring 2014 Dilution refrigerator P ~spring 2014 Large dewar P S S N N Reliquefier P N N EverCool-2 P N N N N Description 4 Available * For details 8 Possible but not a recommended combination please refer to the PPMS- N Not compatible DynaCool S Included in the base system brochure PPMS multi function probe