Attachment_1_Specifications.pdf

Solicitation N00173-19-R-ZL05

Attachment 1

Cryogen-Free SQUID Magnetometer Specifications

1.1 Scope

This specification describes the minimum technical requirements and performance standards for a

Cryogen-Free Superconducting Quantum Interference Device (SQUID) Magnetometer to be installed by the contractor at the Naval Research Laboratory (NRL), Washington, DC. This system will be used in an interdisciplinary research laboratory by NRL personnel to measure the magnetic properties of materials and devices under controlled magnetic field and temperature conditions.

The system must allow for safe and easy operation for the users and other occupants of the facility.

Used equipment in whole or in part is not acceptable in the purchase of this system.

1.2 Installation site

The contractor shall install the system at the U.S. Naval Research Laboratory located in

Washington DC 20375, at a specific location to be designated by the Contracting Officer's

Representative (COR). The NRL will provide 110 VAC single phase and 208 VAC single phase and/or three-phase electrical power, system cooling water, process gases and gas lines at that location for the proper operation of the tool. The contractor shall install the system to the plumbing and electrical fixtures available in the designated location.

1.3 General description and primary components

The requirements are for an automated data acquisition, temperature and magnetic field control platform to perform magnetization measurements of materials and devices. The magnetometer should be a SQUID-based device capable of operating in three measurement modes: (1) DC scan mode, (2) vibrating sample magnetometry (VSM) mode, and (3) AC susceptibility mode. The dewar housing the sample chamber system must not rely on the transfer of liquid helium from a separate storage dewar for refrigerant supply; it must include a pulse tube refrigerator cryocooler and a gaseous helium compressor cooled by a separate fluid-to-fluid heat exchanger for sample space cooling. A sample space oven for high temperature measurement is also required. The magnetic field must be generated in the sample space uniformly by a superconducting solenoid that features additional compensation coils for ultra-low field capability and reside within a magnetically shielded environment. The system must come supplied with sample holders. In situ horizontal rotation of the sample is also required. The system must be modular and allow for the addition of future measurement options and connection of external devices as needed. The system must be computer controlled via user-friendly, menu-driven software.

2.1.1 General cryostat requirements

• Top-loading variable temperature sample space housed within a magnetically shielded cryostat dewar with integrated pulse tube refrigerator cryocooler cold-head

• Helium compressor with at least 20,000 hr compressor adsorber service interval

• Fluid-to-fluid heat exchanger package capable of at least 9 liters/min flow at 28°C and at least 3 liters/min flow at 10°C for cooling of the helium compressor

• Helium liquefaction capacity of at least 9 liquid liters/day

• Initial operating charge of liquid helium produced directly from helium gas within 30 hours to reach steady state and ready for normal system operation.

• After initial cooldown, liquid helium must be replenished by continuously recondensing evaporated helium directly within the dewar

• The system shall not utilize needle valves or require manual adjustment for helium flow control

• The system shall not require a high-vacuum pump for installation, subsequent cool- downs or flow blockage issues

2.1.2 General magnet requirements

• 7 Tesla (or greater) superconducting solenoid magnet with bore axis concentrically positioned with sample measurement space at its center

• Superconducting magnet power supply having bi-polar operation with at least 24-bit resolution

2.1.3 General electronics requirements

•Electronics cabinet

• CAN control electronics.

• Menu-driven control, system logging and data acquisition software running on Intel based i5 or i7 PC running Windows l0, 2 gigabytes of RAM (minimum}, a CD or DVD writer, one

(minimum) user-accessible USB port, keyboard, mouse andmonitor.

• The system must be capable of automated background subtraction to remove the contribution of the sample holder from the measured signal

2.1.3 General parts and logistics requirements

• All cables, hoses and pumps for operation.

• System manuals.

• System user kit containing tools, spares and break-out bridge.

• System unpacking, installation, start-up, training, and acceptance testing.

• Shipping FOB destination

• At least one year system warranty (including parts and labor)

2.2.1 Temperature control performance requirements (without oven)

• Operating range: 1.8 K (or lower) to 400 K (or higher) with smooth control through 4.2 K helium boiling point

• Cooling rate: 30 K/min (300 K to 10 K stable in at most 15 min., typical); 10

K/min (10 K to 1.8 K stable in at most 5 min., typical)

• Temperature stability: +/- 0.5% or better

• Temperature accuracy: lesserof +/-l% or 0.5 K or better

• Sample chamber inner diameter: at least 9 mm

2.2.2 Temperature control performance requirements (with oven)

• Operating range: 300 K (or lower) to 1000 K (or higher)

• High vacuum operation to prevent helium boil-off

• Dedicated sample holder fordirect sample heating

• Temperature stability: +/- 0.5 K (or better)

• Temperature accuracy: better than 2%

• Sample chamber inner diameter: at least 5 mm

2.3.1 Magnetic field control performance requirements

• Magnetic field range: -7 T (or lower) to +7 T (or higher)

• Field uniformity: at least 0.01% over 4cm

• Field charging rate: 4 G/sec (or lower) to 700 G/sec (or higher)

• Field charging resolution: at least 0.33 G

• Remnant field: ~5 G (or less) when oscillating from full field back to zero

2.3.2 Magnetic field compensation requirements

The system must include a sub-system of components to spatially measure and eliminate residual magnetic fields within the sample measurement space using a magnetic field sensor and cancellation coil set, respectively, compliant to the minimum specifications below:

Nulling Specifications:

• Field nulling window of at least ±10 mm measured from center of magnet

• Field uniformity - maximum variation of ±0.05 Gauss (or less) at any point along the magnet axis insidethe nulling window

• Target field range ±5 Gauss (or greater) as determined by magnetic fieldsensor

• Field stability of at least 24 hours

Magnetic sensor specifications:

• Range: at least ±10 Gauss

• Sensitivity: ±0.002 Gauss (or less)

• Accuracy: ±(0.02 Gauss + 0.5% measured.field) or better

Additional Specifications:

• Magnet profiling length of up toat least 50 mm

• High resolution field range of at least ±20 Gauss

• Field resolution: Better than 0.002 Gauss

• Field accuracy: +(0.002 Gauss + 0.5% set field)or better

2.4.1 Magnetization (DC scan mode) performance requirements

• SQUID-based DC magnetometry/susceptibility

• Maximum detectable magnetic moment limit of no less than 8emu

• Lower detection limit below 5 x 10 -8 emu at applied fields less than or equal to 2,500 G

• Lower detection limit below 6 x 10 -7 emu at applied fields above 2,500 G

• Measurement scan range from 0.1 (or less) to 8 mm (ormore)

2.4.2 Magnetization (VSM mode) performance requirements

• SQUID-based vibrating samplemagnetometry

• Lower detection limit below 1 x 10 -8 emu at applied fields less than or equal to 2,500 G with less than 10 seconds of averaging

• Lower detection limit below 8 x 10 -8 emu at applied fields above 2,500 G with less than

10 seconds of averaging

2.4.3 Magnetization (AC susceptibility mode) performance requirements

• SQUID-based AC susceptometer system

• AC driving frequency range: 0.1 Hz (or less) to 1 kHz (or more)

• AC drive amplitude (peak): 0.1 G(or less) up to 10 G (or more)

• AC moment sensitivity: less than or equal to 5 x 10 -8 emu (orbetter)

• AC moment accuracy compared to DC moment value within±1%

• Phase Angle Accuracy within ±0.5°

• Frequency (full spectrum) and temperature (at most 2 K to 400 Kat least) dependencies for samples with moments larger than 2 x 10-6 emu (at most)

− on AC moment: within ±1%

− on phase angle: within ±0.5°

2.5 Sample rotation requirements

The system must allow for samples to rotate around a horizontal axis while present within the sample chamber and measurement region of the magnetometer.

• Capable of sample rotations of up to 360 degrees in 0.1 degree increments orless.

• The rotator must be constructed of special materials to minimize magnetic contribution from the holders.

• The sample rod must have the stepper motor fully integrated into the sample rod.

• Normal operation should allow software control of the sample holder plate with the rotator motor, allowing fully automated sample measurements as a function of angle.

• Minimum sample area size: 4 mm x 4 mm x2 mm

• Angular range: -10° to 370° (one or both directions)

• Angular step size: at least 0.1°

• Reproducibility: less than 1.0° variation with less than l 0° backlash

3. Fluid-to-fluid heat exchanger package

A fluid-to-fluid heat exchanger package that is capable of at least 9 liters/min flow at 28°C and at least 3 liters/min flow at 10°C for cooling of the helium compressor must be included.

4. Optical illumination with tunable light source

The system must possess the ability to optically illuminate a sample with a tunable light source during a magnetization measurement. The equipment should meet the following requirements:

• Include a 100 W short-arc xenon tunable light source (280 - 1100nm) with starter and power supply.

• Include a 120 mm focal length monochromator.

• Include an SMA fiber output

• Include a support arm for cable tension relief.

• Must include one (or both) of the following:

− A fiber optic sample holder probe (UV to visible range) for VSM measurements

− A fiber optic sample holder probe (visible to IR range) for VSM measurements