OptistatTMAC-V Cryofree® optical spectroscopy cryostat

OptistatAC-V Cryofree® optical spectroscopy cryostat

The OptistatAC-V cryogen-free optical cryostat, using pulse tube refrigerator (PTR) technology, is designed to fit all the major spectroscopy applications, offering:

Base temperatures down to 2.8 K without the need for liquid helium
Easy sample change
Low running cost
Large sample space, with a sample in vacuum environment, enabling studies of samples with a wide range of size and geometry
An extensive range of demountable windows for current and future applications

Two models are available with differing cooling power.

Specifications
System components/options
Operation
Applications
Images

Layout and dimensions


OptistatAC-V 12	OptistatAC-V 14

Specifications

	OptistatAC-V 12	OptistatAC-V 14
Cooling technology	PTR
Temperature range	2.8-325 K
Temperature stability	± 0.15 K
Typical cool down time	90 minutes to 4 K	60 minutes to 4 K
Typical cooling power	0.25 W @ 4.2 K 10 W @ 65 K	0.5 W @ 4.2 K 25 W @ 65 K
f number with standard windows	2.4
Compressor adsorber service interval	>20,000 hours
Power consumption - air cooled compressor	3.5 kW	5.3 kW
Power consumption - water cooled compressor	3.3 kW	4.8 kW
Mains power requirements	200, 208/230 VAC 1 phase, 60 Hz 200, 220/240 VAC, 1 phase, 50 Hz	200*, 220/230 or 460 VAC 3 phase, 60 Hz 200/220 or 380/420 VAC 3 phase, 50 Hz
Water flow rate - water cooled compressor only	3 litres/minute	6 litres/minute

* using a transformer, provided for the OptistatAC-V 12

Typical system components

A complete system consists of:

Optical cryostat
Optical sample holder
Windows (up to four radial)
ITC503 temperature controller
Air- or water- cooled compressor
Flexible metal hoses
10-pin connector for the provision of electrical connections to the sample holder and heat exchanger

Options

Remote motor

Enables electrical noise isolation (Electrical isolators-RF, EMI) and easy maintenance of rotary valve, valve plate and motor

Low vibration option

Further reduces vibration on the sample stage
Can be used in combination with the remote motor option

Narrow gap tail option

The OptistatAC-V can be supplied with a narrow gap tail (2 inch outer dimension) for applications requiring integration into an electromagnet

Compressor

Air-cooled or water-cooled compressors are available

Window materials

All windows are demountable and a wide range of window materials is available

Wiring

Special wirings are available on request

The compressor system supplies compressed helium to the cold head through the flexible metal hoses. The gas expands in the cryostat unit to provide refrigeration, by expanding the high-pressure helium to low pressure, and then returns to the compressor unit. The cold head heat exchanger is in good thermal contact with the sample holder.

Precise temperature control is obtained using an ITC temperature controller to drive a heater located near the sample holder, sample temperature being measured using a rhodium iron temperature sensor. The optical cube, which is the lower section of the outer vacuum case, is retained by easily removable clamps to facilitate sample change.

To change the sample, the cryostat is warmed to room temperature, the vacuum released, and the clamp, optical cube and radiation shield (if applicable) removed.

UV / Visible spectroscopy: Experiments at low temperatures reveal the interaction between the electronic energy levels and vibrational modes in solids.

Infrared spectroscopy : Low temperature IR spectroscopy is used to measure changes in interatomic vibrational modes as well as other phenomena such as the energy gap in a superconductor below its transition temperature.

Raman spectroscopy : Lower temperatures result in narrower lines associated with the observed Raman excitations.

Photoluminescence : At low temperatures, spectral features are sharper and more intense, thereby increasing the amount of information available.

SPM, STM, AFM : Low temperatures decrease the thermal noise from the probes and reduce atomic vibrations.