LTL Facilities

SUB mK RESEARCH FACILITIES

The two nuclear demagnetization cryostats of LTL are specialized pieces of equipment which are the flagships of LTL in the Microkelvin research. One of them is used for studies of superfluid 3He in collaboration with researchers from all over Europe, Japan, and Russia. The second one is employed for unique cooling experiments trying to find new superfluid systems in collaboration with researchers from UK and Russia. LTL together with BlueFors Cryogenics (LTL spin-off company) are developing new dry demagnetization cryostat.

SUB 1K RESEARCH FACILITIES AND THERMOMETRY

Altogether nine dilution refrigerators provide the backbone of the low temperature nanophysics research in LTL. These refrigerators typically provide a 8-30 mK base temperature, which is enough for studies of phase coherent, even ballistic transport in nanostructures and for quantum information processing in superconducting quantum circuits. The dilution refrigerators are in frequent use within the Microkelvin program as well as in many other projects with European funding (CARDEQ, ENTS, GEOMDISS, RODIN, SCOPE).

RESEARCH FACILITIES AT LIQUID HELIUM TEMPERATURES

In the range of temperatures 4.2 – 1.2 K, LTL has lots of cryostats with different measurement capabilities, ranging from simple DC electrical measurements to involved microwave measurements for noise, cross-correlations, and vibrations in NEMS resonators.

ROOM TEMPERATURE RESEARCH FACILITIES

Room temperature research facilities are used to characterize samples after fabrication. The equipment include a microRaman setup for local Raman measurements and an atomic force microscope. Using the AFM, surface enhanced Raman can be investigated. In addition, there are setups to measure susceptibility of novel materials at microwave frequencies. These systems are essential for the industrial people who collaborate with the LTL researchers on materials issues, for example, on graphene and nanotubes.

MICRO- AND NANOFABRICATION FACILITIES

The facilities include a production line for e-beam lithography down to 100 nm resolution, operated in a semi-clean-room environment. The facilities are sufficient for basic samples in mesoscopic physics and for nanocarbon devices. The nanofabrication facilities of LTL supplement the infrastructure at Micronova in the sense that cleanliness requirements are not as strict, and more non-standard operations are allowed, and even modifications on the facilities are possible in order to reach the research goals. In this adaptable way the LTL infrastructure can serve users whose needs are often different from the standard ones. The semi-clean-room environment also serves many researchers of Aalto University in their work on nanocarbons. Moreover, the fabrication facilities include equipment for heat treatment, critical point drying, and annealing in order to guarantee the best quality of samples before cool down to mK temperatures.

SERVICE FOR INDUSTRIAL COMPANIES

LTL offers low temperature facilities to industrial companies for testing and developing new cryogenic products. These facilities are important for small companies as well as to industry researchers working in cryogenic applications (Aivon, Nanoway, Picowatt, Elekta Neuromag, BlueFors) since the available cryostats allow these LTL users to quickly try their ideas in cryogenic environment. New advanced dry dilution refrigerators, CBT temperature sensors and cryogenic amplifiers are under development within the TEKES-funded FinCryo-project.

CRYOGENIC AND NANOFABRICATION TRAINING

LTL offers different training in the area of low temperature physics, cryogenics, micro- and nanofabrication.