A custom-built scanning tunneling microscope/ atomic force microscope combined system manufactured by Createc, with a base temperature of 5 K and a base pressure < 1 -10 Torr. The scanner is specially designed to accommodate optical access to the scanner. The chamber has two bucket re-entry windows, and a pair of adjustable lens sets to achieve a ~0.45 numerical aperture and a ~1 um optical resolution. The STM is capable of simultaneously shining a light on the STM junction and collecting light from the other side of the scanner. The scanner is also equipped with a low-temperature current amplifier designed by the SMALL team. The maximum holding time of the liquid He tank is  ~75 hrs.

The wavelength tunable femtosecond light source includes a 40 W 1050 nm Yb: KGW based solid-state pump laser with 1 MHz repetition rate and < 290 fs pulse width, an OPA to generate 650 nm to 16000 nm tunable laser beam, and a THz generation setup with tilted wavefront. Our team is currently constructing the second harmonic generation pathway to extend the wavelength into the ultraviolet regime with a wavelength as short as 325 nm. 

The SMALL team designed and built a He recovery system to recycle the He boiloff from the low-temperature STM-AFM. It's equipped with a Cryomech pulse tube cryocooler (PT410) and is contolled by a program written by the SMALL team. This recovery system has a variable recondensation capacity up to ~8 L/day and helps reduce the year-round He consumption rate of the SMALL lab to < 100 L while continuously running the low-temperature STM-AFM at 5 K. It can be easily adpated for other cryogenic instruments that are sensitive to vibration.

Our lab has two optical microscopes and a sample exfoliation/transfer station for the fabrication of monolayer low-dimensional layered materials. We home-built a UHV heater to anneal the sample up to 500 ℃ at a pressure below 10-10 Torr, to fabricate atomic clean TMD samples. We have also designed a series of K-cell molecular evaporators for the thermal deposition of molecules with different melting points. The lab is also equipped with Residue Gas Analyzers for mass spectrometry and helium leak check. 

Our wet chemistry lab has a series of facilities including two fume hoods to carry out and analyze chemical reactions in solutions. For example, the atomically sharp STM tips in different materials including tungsten, Pt/Ir alloy, and silver are etched here. It also has an ultrasonic cleaner to remove incompatible chemicals from the surface of UHV parts.