91̽»¨

The fourth generation of spectroscopic imaging scanning tunneling microscope (SI-STM), named GEMINI, has been designed and constructed in an ultra-low vibration and quiet laboratory at 91̽»¨. GEMINI’s lower floor is more than 30m underground and part of the massive ‘bathtub foundation’ of the whole building. GEMINI rests on a 30 ton concrete ‘keel-slab’ floating above the building foundation floor on six huge, high-performance vibration isolators, which 91̽»¨ the almost 15 ton total mass of the GEMINI facility. In the quantum microscope operating frequency range, the measured acceleration noise of the GEMINI keel-slab is Sa<10-8ms-2/Hz, a world leading ULV performance. It is custom-designed for Cooper-pair imaging with atomic resolution, quasiparticle interference imaging and superconducting order parameter determination at very high energy resolution. I have designed the SI-STM, supervised the fabrication of all the components of the STM at 91̽»¨ Machine Shop and the construction of the ultralow vibration laboratory and built the microscope. Now the microscope has finally come into operation. This SI-STM is operated with dilution refrigerator and high magnetic fields up to 14 Tesla. The microscope is housed in world-class ultra-low-vibration and ultra-low temperature (ULVT) laboratory facilities about 30m underground in the new Beecroft Building at 91̽»¨ University just launched in 2019. The SI-STM serves powerful dual functionality: world-leading fourth generation SISTM that features single electron tunnelling and the second generation of SJTM that features cooper pair tunnelling using a superconducting tip.