For different end-user research areas, we offer a variety of electrical connection options. In addition to the temperature control, piezoelectric motion control lines provided by default, ColdTABLE also have a wide range of custom options, including electrical connectors for high frequency signals, DC signals, and coaxial signals.

➡ Spatial Configuration of Electric Connector at 4K Ring Area (Function Zone)

➡ List of Electric Connector Plate & Function Parts

❖ “A – Type” Connector Plate

❖ “B – Type” Connector Plate

❖ Function Parts

Based on brilliant cryogenic design and MultiFields cutting-edge temperature controller KELVINION mini, super-reliable temperature performance is one high-light feature of ColdTABLE.

➡ Temperature Control Module of ColdTABLE System

Provide the most reliable temperature state of the system to the end user.

1. Components of Temperature module
– Thermometer, Cernox 1050
– Heater, 50 Ω, max. 50 W

2. Location, temperature module
– The system’s default temperature control module (including thermometer and heater) is mounted directly on the underside of the 4K Sample Plate

3. Meter for temperature control
– “Kelvinion” temperature controller from MultiFields Tech.

4. Upgraded option
– ColdTABLE support at most 4 pcs thermometers installed as customer required.

5. Electrical connections
– All electrical connections are placed at 4K Ring Area.

➡ Temperature stability, better than 2 mK _{@ 4.5 K} & 20 mK _{@ all range}

Temperature fluctuations data covering all workable temperature range.

➡ Cooling time, 180 mins, from 300 K to 5 K

Results from ColdTABLE with no heat load.

Maximum 100 W power output and minimum 300 mK controlled temperature.

MultiFields Technologies designed the “Kelvinion”, a powerful cryogenic temperature controller. It consists of 8 independent high-precision temperature monitoring channels and 2 high-power PID output channel (100 + 50 W), as well as 2 relay output and 2 analog output channel. The PID closed-loop control, Zone mode, variable temperature rate setting and active over-temperature detection, make the Kelvinion mini cryogenic temperature controller a great tool for low-temperature researches.

Key Features

– Temperature range of measurement and control down to 300 mK;
– 8 independent monitoring channels with 0.1 mK resolution (24-bit ADC) ;
– Automatic tuning of the excitation current for higher accuracy and lower heating;
– Supports 1000+ user-defined curves；
– 2 PID output channel with 100 W power output；
– Supports 2 relay and 2 analog signal outputs；
– Supports setting temperature ramp rate；
– PID parameters can be switched according to the zone table for different temperature ranges (Zone mode)；
– Support USB (serial port), LAN and GPIB communications；
– Automatic protections such as heater short and open detection, set point limits are supported.

Vibration level is the most critical parameter for closed-loop cryogenic optical platforms. We make ColdTABLE in
nanometer vibration level.

Setup on ColdTABLE for 3-axis vibration measurement by laser interferometer method.

Methods

In terms of accuracy, laser interferometer is a more accurate method for measuring vibration compared to common capacitors or eddy current sensors. On the other hand, considering that the main use scenario of ColdTABLE is also optical, it is a more appropriate way to directly measure the vibration amplitude by means of laser.

According to the measurement method shown in the figure above, the 3-axis vibration amplitude we obtain is essentially
the vibration of the 4K Cold-Plate relative to the optical platform plane.

Bandwidth of Vibration Results

It is no good to discuss the magnitude of vibration displacement by ignoring the measurement bandwidth. In reality, all
measurement systems have their own fastest sampling frequency, and this fastest sampling frequency itself is equivalent to a low-pass filtering process.

The main motion frequency of the GM cold head is about 1 Hz, but the main motion causes a wide frequency associated
vibration, which leads to vibration components in the spectrum analysis up to several hundred Hertz, so we recommend that the fastest sampling frequency should not be less than 1 kHz (in other words, the cut-off frequency of low-pass filtering should not be less than 1 kHz).

If we want our measured vibration results to be as close to the real experimental situation as possible, it is necessary to ensure that we do not miss the high-frequency components of the vibration. But on the other hand, if we let all the highfrequency signals in, it will produce a lot of electronic noise, and drown out the real vibration information.

Moreover, we strongly do not recommend adding low-frequency cutoff operations (low-frequency high-pass filtering)
when testing vibration. After the low frequency cutoff, a large amount of GM cooler vibration information is missed.

➡ Vibration < 5 nm @ 4.5 K, base temperature

Vibration results with 1 kHz sampling frequency when system hold at 4.5 K.

➡ Vibration (3-axis) < 20 nm @ continuous cooling process

Vibration results with 1 kHz sampling frequency when system in continuous cooling process.

various objectives for stable & long-term working in 4 K environment

*df, chromatic focal shift, Δ = n*λref / (2*NA^2)

The Huygens series of objectives are designed for working at 4.2 K environment, and have as wide as possible apochromatic range. The numerical apertures cover 0.36, 0.6 and 0.9, with corresponding work distances of 1.0 mm, 6.0 mm, and 13.0 mm to satisfy different research purposes.

By utilizing N.A. ~ 0.9 objective, users can enhance experimental spatial resolution and photon collection efficiency, while the ultra-long working distance objective is suitable for diamond anvil cell (DAC), achieving Raman & Fluorescence testing under GPa high pressure.

➡ The Huygens series — simulation data of Focal shift & Strehl ratio

Note： Focal shift: the variation of focal position for different wavelengths relative to λref. Δ = n*λref / (2*NA^2): depth of focus.
Strehl Ratio: the peak intensity normalized to perfect lens for different wavelengths.

Dimension drawing of Huygens 0.9 objective.

Dimension drawing of Huygens 0.6 objective.

Dimension drawing of Huygens 0.36 objective.

MultiFields offer a complete range of low temperature piezoelectric motion solutions covering all the motion elements such as linear, rotary and tilting stages with long travel ranges and scanning units for high resolution and dynamic small range motion needs.

Piezoelectric motion units is one independent product line of MultiFields Tech., more details can be found in Cryogenic Motion.

For universal optical experiments, ColdTABLE supply recommended combinations of piezoelectric motion units.

➡ Default Set

Standard low temperature piezoelectric motion solution, 6mm x 6mm x 6mm motion range with closed-loop control.

➡ Long Travel Range Set

ColdTABLE supplies long travel range set for end-user, 20mm x 20mm in XY plane and 6 mm in Z direction.

➡ Large Load Set

For example, some end-user use this set to perform high pressure experiment, for the diamond anvil cell itself is very heavy.

Schematic of default motion units

1. Component of Motion Set
– Linear25-x, 2 pcs, positioner
– Linear25-z, 1 pcs, positioner
– Scanner25-xy, 1pc, scanner

2. Meters, Motion Controller
– Positioner Controller, NewtonLT.06
– Scanner Controller, ArchemedsLT.03

3. Key Parameters
– 250 g, net load for end-user
– 6mm x 6mm x 6mm, travel range
– 45 mm height
– 17 pins electric contacts in total

Schematic of long travel range motion units

1. Component of Motion Set
– Linear35-x, 2 pcs, positioner
– Linear25-z, 1 pcs, positioner
– Scanner25-xy, 1pc, scanner

2. Meters, Motion Controller
– Positioner Controller, NewtonLT.06
– Scanner Controller, ArchemedsLT.03

3. Key Parameters
– 250 g, net load for end-user
– 20mm x 20mm x 6mm, travel range
– 45 mm height
– 17 pins electric contacts in total

Schematic of large load motion units

1. Component of Motion Set
– Linear35-x, 2 pcs, positioner
– Linear35-z, 1 pcs, positioner

2. Meters, Motion Controller
– Positioner Controller, NewtonLT.06

3. Key Parameters
– 450 g, net load for end-user
– 20mm x 20mm x 10mm, travel range
– 45 mm height
– 17 pins electric contacts in total

➡ Flexible Thermal Link

For the sake of structural rigidity and weight reduction, we chose titanium instead of using high thermal conductivity copper as the main frame in the conventional version. As a result, in the vacuum environment, we can not completely transmit the temperature of the 4K Sample Plate to the sample. In order to solve this problem, we designed flexible thermal conductive parts using oxygen-free copper with high thermal conductivity to ensure that the sample movement is not delayed and the sample temperature can be well lowered to base temperature.

Integrating cryogenic low-vibration techniques with nano-motion, cryogenic objectives, and other technologies to offer a comprehensive solution for cryogenic optical experiments

ColdTABLE System, Specification