Super-fast Characterization at sub-Kelvin Temperature


Super-fast Characterization at sub-Kelvin Temperature

The L-Type Rapid is a unique top-loading cADR system offering continuous cooling at 300 mK and one-shot operation down to 100 mK. Its innovative automatic sample transfer allows for cooling a sample to the minimum temperature in less than three hours, enabling high-throughput screening of scientific samples and rapid prototyping of quantum electronics. For low-temperature investigations of field-dependent physical properties, the L-Type Rapid can be equipped with a 5T sample magnet.

100 mK - 300 K

< 3 hours

300 mK

L-Type Rapid cryostat

Key Benefits

Built for an improved sub-Kelvin experience

Fast sample characterization

The L-Type Rapid features kiutra’s proprietary puck-based top-loading sample exchange mechanism.  This option allows the user to prepare their sample on a sample puck and load it into the cryostat in just a couple of minutes – there is no need to warm up the cryostat. In this way, a sample can be installed and cooled to the base temperature in less than three hours. After completion of the low-temperature tests, the sample can be removed just as quickly, and within a few minutes the next device, prepared on a spare puck, can be loaded. Thus, the L-Type Rapid enables the highest sample turnover for sub-Kelvin studies.

Wide temperature range

ADR systems always come with a heat switch to decouple the solid-state cooling medium from its pre-cooling stage during the demagnetization refrigeration process. In the L-Type Rapid, the latter allows for continuous operation at 300 mK and one-shot cooling down to 100 mK. The weak thermal link provided by the heat switch also allows to carry out heater-assisted continuous temperature sweeps from base to room temperature. In contrast to typical He-based refrigerators, the L-Type Rapid offers simple access to a large temperature range, making additional equipment or accessories for working with very low temperatures obsolete.

Highly modular cooling platform

The L-Type Rapid is a versatile cryogenic platform for basic science and applied quantum research, offering a variety of possibilities to configure the system. The sample puck and cryostat wiring can be chosen to provide up to 4 RF and 40 DC connections, including also low resistance wiring for driving piezo positioners. For samples that are sensitive with respect to magnetic fields, mu metal shielding can be added. To probe magnetic properties, a 5 T sample magnet is available.

Typical Applications

Innovative cooling for state-of-the-art science and technology


With first concepts dating back to the 1980s, superconducting circuits are today one of the most promising technologies in the race to build a universal quantum computer. The key element in superconducting quantum circuits is the Josephson junction – a non-linear element that connects two superconducting islands by a weak link, which can be either an insulating or a metallic barrier. Superconducting quantum circuits offer individual control and readout, and their properties can be engineered by circuit design. During the past two decades, superconducting qubits experienced a rapid improvement of their coherence properties, resulting in the demonstration of several major milestones toward scalable quantum computing. To screen and characterize superconducting thin films and devices more efficiently, kiutra’s L-Type Rapid offers an extremely fast sample cooldown, combined with a large temperature range, and a base temperature as low as 100 mK.  

Schematic depiction of a Q-Bit State in an Energy Diagram and as an electronic circuit
schematid depticion of a race-track memory

Spintronic Devices

Researchers in the field of spintronics study and exploit the spin-charge coupling in metallic systems. Making use not only of the charge carriers’ charge but also of their spin allows, e.g., to build novel devices like racetrack memory or MRAM to save digital data. These technologies promise low-energy information storage, high reliability, performance, and capacity also at room temperature. However, to better understand the underlying physics and to develop novel materials for spintronic devices, low temperatures, high-frequency cabling, and magnetic field control at the sample position are required. The L-Type Rapid offers access to a wide temperature range from 100 mK to room temperature in a single, cryogen-free, and easy-to-use instrument. Optional upgrades such as a sample magnet, and additional RF and DC wiring allow to implement various experimental setups and low-temperature measurements.

Performance Data

Fast and trouble-free operation

Fast sample cooldown

The cumbersome and time-consuming operation of large and complex refrigerators is a bottleneck in the development of novel functional materials as well as next-generation quantum devices. The L-Type Rapid, with its puck-based sample loader, offers a fast and automatic sample cooldown, increasing sample throughput and accelerating the screening of material samples and quantum devices. The figure shows a typical time-temperature curve for our sample puck with a test device mounted, while cooling from room temperature to sub-Kelvin temperatures. In the initial 1.5 hours, the puck is cooled to the cryocooler base temperature. After the puck is fully thermalized, the ADR cooling units can be charged. This process takes approximately 1 hour. Subsequently the demagnetization cooling is started, and the system can be operated either continuously at temperatures as low as 300 mK, or at 100 mK for a limited hold time. Apart from mounting the puck in the vacuum lock, the operation is automatic and can be controlled through our Python-based instrument control software.

Cooldown Curve of the sample puck in an L-Type Rapid Cryostat

Continuous operation at 300 mK

Conventional adiabatic demagnetization refrigerators (ADR) allow only for “one-shot” cooling. By combining multiple ADR units, kiutra’s cryostats can provide both “one-shot” and additionally continuous sub-Kelvin cooling (cADR) independent of the supply with cryogens. In its standard configuration, the L-Type Rapid uses two ADR units to generate continuous cooling. The figure shows the temperatures of both ADR units running in cADR mode at 300 mK. While the first unit cycles between the 4 K main heat bath (provided by the cryocooler) and a temperature below the target temperature, the second unit controls the sample temperature. As a result, the sample stage can maintain a constant temperature of 300 mK with a typical temperature stability <0.1 %, and a slightly reduced stability <2 % when activating its heat switch to initialize the regeneration.

Plot, showing the continuous operation of the L-Type Rapid Cryostat at 300 mK.

Scope of Supply

We deliver turnkey solutions


Sumitomo RP-082B2 closed-cyle pulsetube cryocooler, 1W 4.2K, 40 W @ 45 K
Sumitomo F70H water-cooled indoor helium compressor, 20 m flexlines
Two ADR units for one-shot continunous operation:
  • 2 ADR magnets
  • 2 Heat switches
  • 2 Cooling media
Wide range pressure gauge
Integrated passive quench protection
User ports for custom integration:
  • 2 x ISO-F 100
  • 1 x ISO-KF 25

Instrument Control

Custom 19” electronics rack
kiutra Modular Control Unit (MCU):
  • Base Module
  • Power Module
  • Drive Module
  • 2x Load Module
  • Gas Handling Modul
kiutra Compressor Control Unit (CCU)
Temperature monitor
Temperature controller
Calibrated temperature sensor on sample stage
Temperature sensors on cryocooler cold stages and first ADR unit
Sample heater and warm-up heater
User PC with pre-configuration Python-based instrument control software and high-definition display
2x Digital high frequency magnet power supply
User breakout
Filtered temperature sensor breakout
Photo of the top of the L-Type Rapid cryostat showing the open sample loader and the sample cage inside

Standard Wiring

40 DC wires

Gas Handling

Pumping, purging and venting of cryostat and Sample Changer airlock chamber
Oil-free roughing pump
Turbomolecular pump

Sample Changer

Airlock Chamber with motorized sample transfer
Sample puck transfer cage
Additional pressure gauge
1 Sample Puck
1 Sample Puck Testing Station
ISO-F 100 Gate Valve


L-Type Rapid

System size (cm)
(w x l x h)
cryostat (sample changer open)
94 x 94 x 232
60 x 80 x178
45 x 53 x 63
System weight (kg)cryostat< 600
Residual field at sample stage (mT)< 0.05 (0.5 Gauss, 50 µT)
Vibration (µm)< 10 µm
Size of Sample Puck (mm)diameterø 36
Sample cooldown time (hours)300 K – 4K
4 K – 0.1 K
total 300 K – 100 mK
< 1.5
< 3
Cooldown time (hours)cryostat< 42
Temperature range (K)0.1 – 300
Continuous temperature control (K)0.3 – 300
Cooling power (µW)@500 mK
@ 1K
Operation time (hours)@100 mK
@200 mK
Temperature stabilitytypical
while switching stages
< 0.1 % or <0.5 mK
< 2 %

Available Options

Accessories for your individual cryogenic requirements

5 Tesla sample magnet

Smooth bipolar operation to study magnetic properties

Up to 4 RF connections on a puck

and up to 40 DC lines

Magnetic shielding

to investigate and operate sensitive quantum electronics or superconductors
Photograph of the L-Type Rapid Sample Puck

Do You Need Further Information?

Our team has extensive experience in many fields of low-temperature research. We are keen to learn more about your requirements and support you in finding your optimal cooling solution.
Get our brochure with the benefits and key specifications of the L-Type Rapid.