The Lab

Located in the basement of the Materials Research Laboratory at the University of Illinois, our lab houses four scanning tunneling microscopes and two molecular beam epitaxy growth chambers. These state of the art machines allow for immediate and in depth study of the most interesting material systems. Our facilities allow for a diverse range of studies, whether it be of a thin film grown in one of our MBE chambers or a single crystal grown by a collaborator.

All of our STM’s are built with a combination of Unisoku parts and parts made in house. The MBE’s are entirely homemade, built by former graduate student Kane Scipioni (MBE 1) and current graduate student Guannan Chen (MBE 2).

STM 1: 300mK, 11T

The premier STM in the Madhavan Lab, this STM is capable of achieving a temperature of 300mK and a magnetic field of 11 Tesla. Enclosed in a soundproof room, this instrument is capable of taking high-quality low-noise measurements for several days at a time. Typically used to study cleaved samples, this is STM is also used to examine superconducting thin films grown within the group.

STM 2: 4K

Also called the Hybrid STM within the group, this STM is internally praised for it’s stability and low-noise levels. Operating at liquid helium temperatures and enclosed within a soundproof room atop a tonne of granite, this STM has been responsible for some of the group’s highest resolution measurements. At times this STM has had a small growth chamber attached, giving it the “Hybrid” name.

STM 3: 2K, 7.5T

Repurposed from the upgrade of STM 1, this STM might be the first thing you see as you walk into the lab. Capable of reaching 2K with a 7.5 T magnetic field, this STM has been busy since its design and assembly just a few years ago. Enjoy the view while you can, as there are plans to enclose this STM in a soundproof room soon.

STM 4: 4K Tabletop

This STM closely resembles a commercial Unisoku design and is notable for its very low helium consumption. Used especially for thin film growth, the ease of use and optical approach make it ideal for characterization of thin films grown within the group. Additionally, the electronic connections of this STM were designed to facilitate gating of thin films, an important research thrust of the group.

STM 5: 300mK, 3D magnetic field (1T, 4T, 9T)

As the newest STM in the Madhavan Lab, STM 5 features the ability to apply a magnetic field from 3 different directions with 1T, 4T and 9T, respectively. The STM 5 is currently undergoing the final table balancing work in the other sounderproof room.

MBE 1:

The first MBE growth chamber of the group, this MBE specializing in the growth of topological samples and tellurides. Current sources include Te, Bi, Sn, W, Sb and SnTe. Sources can be changed to match the needs of a research project. Crystal growth can be monitored in-situ by RHEED.

MBE 2:

Packed with seven sources for growth, this MBE has a specially designed sample holder to enable collaboration with other research groups at UIUC. While MBE 1 focuses on the growth of tellurides, this MBE focuses on the growth of selenides. It also has a RHEED gun that enables in-situ monitoring of sample growth.