Cryogen-free dilution refrigerator with a 9-1-1 vector magnet

We are seeking to purchase a dry, cryogen free, cryostat for electronic transport measurements of nano-electronic device such a graphene etc. at ultra-low temperatures (<10mK) and direction dependent magnetic fields (vector magnet B = 9-1-1T). The instrumentation shall permit a device environment with a stable (<5mK fluctuations) ultra-low base temperature (T ~ 10mK) and rapid and continuous temperature control from base temperature up to T ~ 10K. The dilution refrigerator system must be equipped with full quantum transport measurement capabilities. This entails DC transmission lines, RF lines and filters and breakout boxes. The specificity of this dilution refrigerator system will be its vector magnet which will allow to apply direction dependent magnetic fields (9-1-1T). The system should also have a fast sample loading mechanism, that allows a fast sample turn around time, without the need to warm up the entire system.

Quantum materials are novel systems, engineered in laboratories, which host strong enough electronic interactions to display quantum phenomena such as superconductivity, correlated insulating states and magnetism with tremendous technological applications. These phenomena emerge when the electronic interaction dominate over the thermal fluctuations of the system, i.e. at mK temperatures. Experimentally, these temperatures are reached in dilution refrigerator systems. Consequently, we aim to add such a dilution refrigerator, capable of a base temperature of 10 mK and equipped with a 9-1-1T vector superconducting magnet. The 9-1-1T vector magnetic field will allow us to introduce a new quantizing energy scale to the material, and thus to tune the electronic interaction. In particular, the ability to direct the magnetic field along different sample direction will allow to decipher many quantum phases from another. For example tuning the magnetic field direction parallel to the sample direction of a magic graphene device, allows to tell whether its ground state is orbital or ferromagnetic.
This refrigerator system will thus open a completely new axis of research. It will allow to probe the electronic response to the temperature and field constraints through 48 highly-filtered DC transmission lines, 8 RF lines that are designed to suppress electromagnetic heating of the electrons with an output integrated in our measurement setup made of an array of DC pre-amplifiers and lock-in amplifiers. The fast loading mechanism is crucial to optimize our usage of this system by greatly reducing loading times. Finally, we wish to buy a cryogen-free system both for its simplicity of usage and low cost of operation.