Micro-PL Cryostat: CS204*F-DMX-20-OM
The CS204*F-DMX-20-OM is our ultra low vibration closed cycle cryostat for optical microscopy applications, such as micro-photoluminescence (Micro-PL).
The DMX-20 interface opens up a wide range of capabilities never before possible with a closed cycle cryocooler. The Micro-PL cryostat uses a helium exchange gas to decouple the sample space from the cold tip of the DE-204 cryocooler. This prevents almost all vibration from being transmitted to the sample space. Scientists have demonstrated vibration levels as low as 3-5 nm with our Micro-PL cryostat.
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 a downward orientation of the cold tip to facilitate convective cooling of the exchange gas.
- Micro-photoluminescence (Micro-PL)
- Quantum dots
- Low vibration optical experiments
- Magneto-optical Kerr effect (MOKE)
- Ultra low vibrations (3-5 nm)
- Supports working distances as small as 1.5 mm
- Continuously adjustable sample holder (1.5 - 7 mm)
- Low profile windows
- Cold tip down orientation
- Fully customizable
- Cold head (DE-204AF)
- Compressor (ARS-4HW)
- 2 helium hoses
- DMX-20 ultra low vibration interface
- Aluminum vacuum shroud with one window port for optical microscopy and electrical experiments
- Nickel plated OFHC copper radiation shield
- 1 high purity quartz window
- Instrumentation for temperature measurement and control:
- 10 pin hermetic feedthrough
- 50 ohm thermofoil heater
- Silicon diode sensor curve matched to (± 0.5 K) for control
- Calibrated silicon diode sensor (±12 mK) with 4 in. free length for accurate sample measurement
- Sample holder for micro-spectroscopy experiments
- Temperature controller
Options and Upgrades
- Transmission experiment upgrade
- Rotatable sample platter upgrade
- Magnet post upgrade
- 4 K cold head (0.2 W @ 4.2 K)
- 5.5 K cold head (3 W @ 10 K)
- Turbo upgrade for faster cooldown times
- High temperature interface (not required with the DMX-20 interface, but helpful for high temperature performance)
- Very high temperature interface
- Custom temperature sensor configuration (please contact our sales staff)
- Custom wiring configurations (please contact our sales staff)
- Window material upgrades (custom materials available)
- 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 transferred to the sample space. Scientists have demonstrated vibration levels as low as 3-5 nm 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 the sample space.
5. Convective pockets of helium exchange gas cool the sample space.
6. The sample is only in contact with the X-20 interface.
7. Windows provide access for optical experiments.
8. The X-20 interface is mounted directly on a (user provided) vibration isolation table.
The DE-204SF 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-204AFcold head is a rugged workhorse built with power and durability in mind, achieving temperatures below 9 K with 2 W of cooling power at 10 K.
The DE-202PF 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 355 K temperature of our cryocoolers.
450 K The Easy Way
Our 450 K interface is a simple semi-permanent addition to the cold tip that expands the upper sample temperature range by 95 K utilizing most of the same instrumentation as our standard cryocoolers.
800 K - Pouring on the Heat
Our specially designed 800 K 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.
Our technicians painstakingly wrap each cold head for optimum thermal anchoring. We offer you the choice of a variety of wiring options, from our standard offerings of single strand copper and low noise coaxial wiring packages to any number of custom wiring configurations.
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 RTDs for accurate high temperature measurements.
Our wide selection of wiring and instrumentation is matched by an equally wide selection of temperature controllers from Cryocon, Lake Shore, and Scientific Instruments.
The water cooled ARS-4HW compressor that powers the DE-204 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 100 feet away.
The ARS DE-204 Closed Cycle Cryocooler operates on a pneumatically driven Gifford-McMahon refrigeration cycle that is both mechanically simple and robust.
12,000-Hour Maintenance Cycle
Over time the internal components of the cold head begin to wear. Eventually the performance of the cold head will decline and some time 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 can purchase a service kit for our 10 K and 5.5 K 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.
|DE-204||Closed Cycle Cryocooler
|Refrigeration Type||Pneumatically Driven Gifford-McMahon Cycle
Low Vibration Helium Exchange Gas
(Tip down operation only)
|Liquid Cryogen Usage||None, Cryogen Free|
|DE-204AF||< 10 K - 350 K
DMX-20-OM interface adds 4-5K to base temperature
|DE-204SF||< 4.2 K - 350 K
DMX-20-OM interface adds 4-5K to base temperature
|DE-204PF||< 5.5 K - 350 K
DMX-20-OM interface adds 4-5K to base temperature
|With 800 K Interface||(Base Temp + 2 K) - 800 K|
|With 450 K Interface||(Base Temp + 2 K) - 450 K|
|*Based on bare cold head with a closed radiation shield, and no additional sources of experimental or parasitic heat load.|
|Diameter||19 mm (0.75 in)
7.8 mm (0.31 in) clear view with transmission upgrade
|Height||1.5 - 7 mm (0.059-0.27 in)
Continuously adjustable sample to window distance.
|Sample Holder Attachment||1/4-28 screw|
|Sample Holder||View our Sample Holder Collection|
|Window Ports||1 (2 with transmission option)|
|Diameter||25.4 mm (1 in)|
|Clear view||23 mm (0.9 in)|
|Window Material||View our Wide Selection of Window Materials|
|Temperature Instrumentation and Control (Standard)-|
|Heater||1 - 50ohm 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 Skirt||Bolt-on, Stainless Steel|
|Pump out Port||1 - NW-25|
|Instrumentation Wiring||Contact our sales staff for wiring options|
|Length||39 mm (1.52 in) sample platter thickness|
|Diameter||127 mm (5 in) at the sample platter (at the sample space)|
|Width||127 mm (5 in) at the sample platter (at the sample space)|
|Material||OFHC Copper, Nickel plated|
|Optical Access||1 (2 with transmission option(customer specified)|
|Overall Length||645 mm (25.4 in)|
|Motor Housing Diameter||114 mm (4.5 in)|
|DMX-20 Sample Vibrations-|
|Independent Mounting||3 - 5 nm|
|Direct Soft Mount||< 140 nm|
DMX-20 Vibration Levels
|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 K||< 4 K|
|Cooling Capacity-||4.2 K||-||-||-||-||-||-||0.2 W||0.16 W|
|10 K||2 W||1.6 W||2.7 W||2.2 W||3 W||2.4 W||4 W||3.2 W|
|20 K||9 W||7.2 W||12 W||9.6 W||8 W||6.4 W||8 W||6.4 W|
|77 K||17 W||14 W||23 W||18.4 W||14 W||11 W||14 W||11 W|
|Radiation Shield Cooling Capacity||18 W||14 W||24 W||19 W||18 W||14 W||18 W||14 W|
|(1st Stage Cooling Capacity at 77 K)|
|Maximum Cylinder Temperature||355 K||355 K||355 K||355 K|
|Cooldown Time-||20K||30 min||36 min||25 min||30 min||40 min||48 min||40 min||48 min|
|Base Temperature||60 min||72 min||50 min||60 min||90 min||96 min||90 min||108 min|
|Weight||Expander||7.7 kg (17 lbs)||7.7 kg (16 lbs)||7.7 kg (16 lbs)||7.1 kg (16 lbs)|
|Standard Voltage||Min||208 V||208 V||208 V||190 V||208 V||208 V||208 V||190 V|
|Max||230 V||220 V||230 V||210 V||230 V||220 V||230 V||210 V|
|Power Usage||Singe Phase||3.6 kW||3.0 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||73 kg (137 lbs)||73 kg (160 lbs)||73 kg (137 lbs)||73 kg (160 lbs)|
|Typical Maintenance Cycle||12,000 hours||8,000 hours||12,000 hours||12,000 hours|
Ultra Low Vibration Cryostat
Click on the images for full size.
DMX-20-OM 0 to 90 degree rotatable sample holder
Courtesy of: Mr. Donghyun Kim
Installed for micro-photoluminescence experiments, with continuously adjustable sample-to-window distance for short focal length experiments.