CS202*F-DMX-20B
- Overview
- Specifications
- Drawings
- Pictures


The CS202*F-DMX-20B is our ultra low vibration closed cycle cryostat for UHV applications. The ARS manufactured DMX-20B interface, like our "B" series cold heads, is a True UHV (10-11 Torr) system where all of the rubber o-ring seals have been replaced with welded joints and metal seals. A CF flange is directly welded to the interface.
The DMX-20B also has the advantage of being easily bakeable to 200 C because the DE-204 cold head can be quickly removed from the DMX-20B interface without breaking vacuum.
The DMX-20 interface opens up a wide range of possibilities never before possible with a closed cycle cryocooler. The CS202*F-DMX-20-OM uses a Helium exchange gas to decouple the sample from the cold tip of the DE-202 cryocooler. This prevents almost all vibration from being transmitted to the sample. Scientists have demonstrated vibration levels as low as 3-5nm with the CS202*F-DMX-20.
Because the exchange gas is inherently less efficient than cooling by conduction the base temperature of the sample will be 1-2 K higher than the cryocooler. Additionally the DMX-20 interface requires the cold tip down orientation to facilitate convective cooling of the exchange gas.
Applications
- Low Vibration UHV applications
- Microscopy applications
- Surface Science
- Nanomaterials
Features
- Ultra Low Vibrations (3-5 nm)
- True UHV (10-11 Torr)
- Bakeable to 200 C with cold head removed.
- Open Sample space
- Cold tip down orientation
- Fully Customizable
Typical Configuration
- Cold head (DE-202AF)
- Compressor (ARS-2HW)
- 2 Helium hoses
- DMX-20 Ultra Low Vibration Interface
- 6" rotatable CF flange
- Nickel plated OFHC copper radiation shield terminating 0.125" short of the cold tip.
- Instrumentation for temperature measurement and control:
- 10 pin UHV feedthrough
- 50 ohm thermofoil heater
- Silicon diode sensor curve matched to (± 0.5 K) for control
- Calibrated silicon diode sensor (±12 mK) with 4in free length for accurate for sample measurement
- Wiring for electrical experiments:
- 10 pin feedthrough
- 4 copper wires
- Sample holder for optical and electrical experiments
- Temperature controller
Options and Upgrades
- 4.5" CF flange available but uses non standard ID and may not fit existing chambers
- 8" CF flange available
- 4 K Cold head (0.2 W @ 4.2 K) CS204SE-DMX-20 (DE-202S not recommended)
- 6 K Cold head (3 W @ 10 K) CS204PE-DMX-20 (DE-202P not recommended)
- Turbo upgrade for faster cooldown times
- 450 K High temperature interface
(Not required with the DMX-20 interface, but the 450K interface is helpful for high temperature performance) - 800 K High temperature interface
- Custom temperature sensor configuration (please contact our sales staff)
- Custom wiring configurations (please contact our sales staff)
- Sample holder upgrades (custom sample holders available)
The ARS Advantage

The X-20 interface uses a Helium exchange gas to decouple the sample space from the cold tip of the cryocooler. This prevents almost all vibration from being transmitted from being transferred to the sample space. Scientists have demonstrated vibration levels as low as 3-5nm with the CS202*E-DMX-20.
1. The Cryocooler is supported by a Floor stand
2. The soft rubber bellows minimize the vibrations transmitted to the sample while keeping in the Helium exchange gas.
3. The X-20 interface has no contact with the cryocooler except through the rubber bellows.
4. The Cold tip has 10-30 micron vibrations (depending on CCR model) but no direct contact with sample space.
5. Convective pockets of Helium exchange gas cools the sample space.
6. The Sample only in contact with X-20 Interface
7. Windows for optical Experiments
8. The X-20 interface is mounted directly on a (user provided) Vibration Isolation Table

The DE-204SE cold head is a precision machine carefully tuned to achieve temperatures below 4 K with 0.2 W of cooling power at 4.2 K.
The DE-202AEcold head is a rugged workhorse built with power and durability in mind achieving temperatures below 9 K with 0.5 W of cooling power at 10 K.
The DE-204PE cold head is a hybrid of the the 4 K and 10 K philosophies achieving a balance that exhibits the best of both worlds, with temperatures below 5.5 K and 3 W of cooling power at 10 K.
Our high temperature interfaces use a unique combination of mechanical and thermodynamic properties to create a high temperature thermal disconnect between the cold head and the sample space. This allows for heating of the sample space far in excess of the maximum 355K temperature of our cryocoolers.
450K The easy way
Our 450K interface is a simple semi-perminant addition to the cold tip that expands the upper sample temperature range by 95K utilizing most of the same instrumentation as our standard cryocoolers.
800 K Pouring on the Heat
Our specially design 800K interface goes beyond the standard techniques to provide a unique system that maximizes thermal conduction at low temperatures while minimizing heat transfer at high temperatures. Beyond the safe operating temperature of Silicon Diodes the standard sensors are replaced with E-type Thermocouples and Platinum RTDs.

From our standard offerings of single strand copper and low noise coaxial wiring packages, to any number of custom wiring configurations, our technicians painstakingly wrap each cold head for optimum thermal anchoring.
Typical instrumentation for temperature measurement and control include, one 50 ohm thermofoil heater, one curve matched silicon diode for rough temperature control, and one free length calibrated diode for direct attachment to the sample or sample holder for accurate temperature measurement. Silicon diode sensors are favored heavily for most standard applications, because of their low cost, durability, and stability, but we do offer a wide variety of other sensors for different applications such as Cernox sensors for high magnetic fields, E-type thermocouples for 4 K - 800 K measurements, and Platinum RTD's for accurate high temperature measurements.
Our wide selection of wiring and instrumentation is matched by an equally wide selection of temperature controllers from Cryocon, Lakeshore, and Scientific Instruments.

Whether the measurement is optical or electrical in nature, the sample large or small, we have a sample holder for almost any measurement. The CS202*F-DMX-20B can accept all but our largest sample holders. As will all of our cold fingers the DMX-20 interface has a 1/4-28 threaded hole on the cold tip to mount the sample holder. So even if you do not find what you need from our wide variety of sample holders there is always the option of attaching a custom sample holder.

The water cooled ARS-2HW compressor that powers the DE-202 Series Cold heads has many benefits that are amplified in small laboratory settings. The water cooling redirects heat energy that would otherwise be dumped into the lab, by a large cooling fan. The lack of a large cooling fan also dramatically reduces the noise of these compressors (only 60 dBA). Additionaly with minimum air circulation, the air currents and dust are kept to a minimum. The high efficiency heat exchanger results in low water usage, and saves space inside the compressor giving it a small footprint. When water is not available our Coolpac™ remote recirculation system can send cooling water from up to 100ft away.

The ARS DE-202 Closed Cycle Cryocooler operates on a pneumatically driven Gifford-McMahon refrigeration cycle that is both mechanically simple and robust.
12,000 Maintenance cycle
Over time the internal components of the cold head begin to wear. Eventually the performance of the cold head will decline and sometime after 12,000 hours certain internal components need to be replaced or refurbished. With Most Closed cycle cryocoolers the only option is to send the cold head back to the manufacturer for service.
A Second Option
The Simplicity of the ARS pneumatically driven cryocooler allows for another option. Our customers have the option of purchasing a service kit for our 10K and 5.5K cryocoolers that replaces all of the worn components. This service kit can be ordered ahead of time and reduce down time to a matter of hours instead of weeks.
DMX-20B Specifications
| Cooling Technology- | ||
|---|---|---|
| DE-202 | Closed Cycle Cryocooler |
|
| Refrigeration Type | Pneumatically Driven Gifford-McMahon Cycle | |
| Liquid Cryogen Usage | None, Cryogen Free | |
| Temperature*- | ||
| DE-202AF | < 10 K - 350 K DMX-20 interface adds 1-2K to base temperature |
|
| DE-202SF | Not Recommended, see CS204*E-DMX-20 for 4K option |
|
| DE-202PF | Not Recommended, see CS204*E-DMX-20 for 5.5K option |
|
| With 800 K Interface | (Base Temp + 2 K) - 800 K | |
| With 450 K Interface | (Base Temp + 2 K) - 450 K | |
| Stability | 0.1 K | |
| *Based on bare cold head with a closed radiation shield, and no additional sources of experimental or parasitic heat load. | ||
| Sample space- | ||
| Diameter | Large Open radiation shield |
|
| Height | Large Open radiation shield |
|
| Sample Holder Attachment | 1/4-28 screw | |
| Sample Holder | View our Sample Holder Collection | |
| Optical Access- | ||
| Window Ports | N/A | |
| Diameter | N/A | |
| clear view | N/A | |
| #/F | N/A | |
| Window Material | View our Wide Selection of Window Materials | |
| Temperature Instrumentation and Control (Standard)- | ||
| Heater | 1 - 50 ohm Thermofoil Heater Anchored on Cold Tip | |
| Control Sensor | 1 - Curve Matched Silicon Diode | |
| Sample Sensor | 1 - Calibrated Silicon Diode | |
| Custom Instrumentation | Contact ARS for available Options | |
| Instrumentation Access- | ||
| Instrumentation Skirt | Welded Stainless steel | |
| Pump out Port | 1 - NW-25 | |
| Instrumentation Ports | 2 - mini CF 1.33in | |
| Instrumentation Wiring | Contact our sales staff for wiring options | |
| Vacuum Shroud- | ||
| Material | N/A | |
| Length | N/A | |
| Diameter | N/A (at the sample space) | |
| Width | N/A (at the sample space) | |
| Radiation Shield- | ||
| Material | OFHC Copper | |
| Attachment | Threaded | |
| Optical Access | Open end Radiation shield terminates 0.125" short of cold tip (customer specified) |
|
| Cryostat Footprint- | ||
| Overall Length | 590 mm (23.24 in) 295 mm (11.63 in) standard flange in tip length |
|
| Motor Housing Diameter | 114 mm (4.5 in) | |
| Rotational clearance | 200 mm (8 in) with "G" configuration | |
| Chamber Interface- | ||
|---|---|---|
| Flanges | CF, ISO | |
| Size | 4.5", 6", 8", 10" (4.5" CF flange non standard may not fit all chambers) |
|
| DMX-20 Sample Vibrations- | ||
| Optimal Mounting | 3 - 5 nm | |
| Direct Mount Dampeners | < 140 nm | |
DMX-20 Vibration Levels

Cryocooler Specifications
| Cryocooler Model | DE-202AE | DE-202A(T)E | DE-202PE | DE-202SE | |||||
|---|---|---|---|---|---|---|---|---|---|
| Frequency | 60 Hz | 50 Hz | 60 Hz | 50 Hz | 60 Hz | 50 Hz | 60 Hz | 50 Hz | |
| Base Temperature | < 9 K | < 9 K | < 9 K | < 9 K | < 5.5 K | < 5.5 K | < 4.2 K | < 4.2 K | |
| Cooling Capacity- | 4.2 K | - | - | - | - | - | - | 0.1 W | 0.08 W |
| 10 K | 0.5 W | 0.4 W | 0.7 W | 0.56 W | 1 W | 0.8 W | 1.2 W | 1 W | |
| 20 K | 2.5 W | 2 W | 3.7 W | 3 W | 2.3 W | 1.8 W | 2.3 W | 1.8 W | |
| 77 K | 4 W | 3.2 W | 6 W | 4.8 W | 3.5 W | 2.8 W | 4 W | 3.2 W | |
| Radiation Shield Cooling Capacity | 10 W | 8 W | 15 W | 12 W | 10 W | 8 W | 10 W | 8 W | |
| (1st Stage Cooling Capacity at 77K) | |||||||||
| Maximum Cylinder Temperature | 355 K | 355 K | 355 K | 355 K | |||||
| Cooldown Time- | 20K | 50 min | 60 min | 35 min | 42 min | 60 min | 72 min | 60 min | 72 min |
| Base Temperature | 70 min | 84 min | 50 min | 60 min | 90 min | 108 min | 90 min | 108 min | |
| Weight | Expander | 7.1 kg (16 lbs) | 7.1 kg (16 lbs) | 7.1 kg (16 lbs) | 7.1 kg (16 lbs) | ||||
| Compressor Model | ARS-2HW | ARS-4HW | ARS-2HW | ARS-4HW | |||||
| Standard Voltage | Min | 208 V | 208 V | 208 V | 190 V | 208 V | 190 V | 208 V | 190 V |
| Max | 230 V | 220 V | 230 V | 210 V | 230 V | 210 V | 230 V | 210 V | |
| Power Usage | Singe Phase | 1.3 kW | 1.2 kW | 3.6 kW | 3.0 kW | 3.6 kW | 3.0 kW | 3.6 kW | 3.0 kW |
| Dimensions: | L | 483 mm (19 in) | 483 mm (19 in) | 483 mm (19 in) | 483 mm (19 in) | ||||
| W | 434 mm (17.1 in) | 434 mm (17.1 in) | 434 mm (17.1 in) | 434 mm (17.1 in) | |||||
| H | 516 mm (20.3 in) | 516 mm (20.3 in) | 516 mm (20.3 in) | 516 mm (20.3 in) | |||||
| Weight | Compressor | 62 kg (137 lbs) | 73 kg (160 lbs) | 73 kg (160 lbs) | 73 kg (160 lbs) | ||||
| Typical Maintenance Cycle | 12,000 hours | 8,000 hours | 12,000 hours | 12,000 hours | |||||
CS202*F-DMX-20B
Full Cryostat
Ultra Low Vibration, Ultra High Vacuum
CS202*F-DMX-20
Typical DMX-20 Installation
ARS-2HW
Compressor


