PRESENTATION OF THE PLATFORM
The physical measurement platform was born out of the need expressed by several laboratories at the university (LPS, ICMMO, IEF) for a versatile system to measure the physical properties of matter. These laboratories jointly purchased two commercial devices from the company Quantum Design, a PPMS in 2009 and a SQUID magnetometer (MPMS) in 2013. These systems allow the study of transport properties (resistance, Hall effect) or thermodynamic properties (specific heat, magnetic properties) on various samples, making it possible to study a vast field of physical problems in condensed matter: superconductivity, frustrated magnetism, thermoelectric effect, nano-magnetism, etc.
These measurements are an essential complement to the photoemission (ARPES), X-ray spectroscopy and scattering, transport, NMR, µSR and magnetic measurements carried out by the project’s participants. The versatility of this platform and its ergonomics allow for shared use, including by trainees, short-term visitors or students. In addition, this platform has an important role to play in characterising samples, enabling the improvement of the synthesis of new materials. In addition to the standard use of the platform, several users have invested in the development of new experiments, allowing physical studies impossible in the usual configuration (contact point spectroscopy, nano volt measurements, very low temperatures, measurements under pressure). Recently the platform has acquired a new equipment, a Bluefors Helium Free dilution with a magnetic vector field to extend the study possibilities to very advanced needs. This project has been supported by the following institutions: LPS – CSNSM – C2N – LAC – LLB – GIS – SQUAP (Paris Diderot) – LPA(ENS).
Due to its versatility, this platform offers users a unique structure at the university, allowing a wide range of complementary measurements for the study of condensed matter. The variety of physical results obtained and the projects that we are going to present show the interest of this platform for its numerous users.
1 –GOVERNANCE AND SCIENTIFIC aniMATION
This platform does not require a large management structure. Decisions are taken in consultation with the users. Meetings between users are organised regularly (one per year). The aim of these meetings is to inform users of several aspects: the rules for booking and using the platform, the fees for each slot, recent experimental developments available to users, the various physical possibilities that the platform offers, and to identify the interest in developing options that are not yet available. Training of new users is done on an ongoing basis.
This platform is installed in a dedicated room of the LPS. In order to allow easy access to users from other laboratories, including out of hours, access cards can be requested. In addition, a VPN remote access is installed on all computers in the room, to allow all users to connect from outside and control their experiment. This remote access also allows for remote troubleshooting, either by the platform managers vis-à-vis the users, or by Quantum Design vis-à-vis the managers when there is a technical problem. These different possibilities have been useful several times in recent years…
In order to enable better communication between users, several tools have been put in place:
- two mailing lists : firstname.lastname@example.org and email@example.com, in order to communicate effectively with users ;
- a website containing all the useful information for users and presenting the platform to the outside world: http://hebergement.u-psud.fr/mesuresphysiques. This site allows reservations to be made and the use of the PPMS and MPMS to be managed by the various players. In addition, this platform is obviously listed on the university’s website (http://www.u-psud.fr/fr/la_recherche/plateformes-technologiques.html).
2 – TRAINING THROUGH RESEARCH / CONTRIBUTION TO TEACHING
The versatility and ease of use of the equipment on this platform make it an ideal tool for introducing students to a modern research environment. This platform is used by the M2 ICFP condensed matter course students to do full-days practical work, during which students can measure quantum oscillations in resistivity and magnetization measurements. Beyond the physics, this is an opportunity to show students how a laboratory works in a situation at a crucial moment in their studies.
This platform is also used on a more occasional basis during training days for high school physics teachers, days organised at the LPS with the aim of bringing teachers closer to the world of research. Visiting this platform allows them to better understand the world of scientific research.
A stated objective of this platform is to allow many users of all levels to make interesting physical measurements. We believe that this objective has been achieved; over the last two years, in addition to researchers and teacher-researchers, there have been around 30 non-permanent users (trainees, PhD students and post-docs) who have been able to conduct physical studies. This opening up to non-permanent staff is a success for this platform, as time is often short for these short contracts, and obtaining results is critical for their career.
3 –HUMAN RESOURCES ASSOCIATED WITH THE OPERATIONs au fonctionnement
The structure has the following staff: An assistant engineer of the LPS, Jean-Pierre DALAC (with a quotient of 50%), is responsible for its day-to-day management, ensuring its maintenance, and welcoming, training and accompanying users. A research engineer, Irek MUKHAMEDSHIN (with a quotient of 20%), is responsible for developing improvements via options that are not currently available. The scientific monitoring of the platform is managed by Miguel MONTEVERDE (with a quotient of 10%), lecturer at the LPS.