A high-temperature superconducting (HTS) magnetic lens developed by the Institute of High Energy Physics (IHEP) for Shanghai Jiaotong University completed magnetic field measurement on January 7th, 2016, showing that the lens meets its design requirements.
The HTS lens will be used in an accelerator-based ultrafast transmission electron microscope capable of producing a full field image in a single shot, with simultaneous picosecond temporal resolution and nanometer spatial resolution. Transmission electron microscopes have played an important role in probing molecules, atoms, crystals and innovative new materials with atomic resolution.
This will be the first HTS lens used for an electron microscope. HTS tapes made by a Chinese company were used to wind the coil. The HTS magnet uses conduction-cooling with one pulse tube refrigerator, so no liquid helium or nitrogen is used. The maximum operating temperature is about 50 K. The HTS lens will increase the resolution of the electron microscope, reduce the overall size and weight of the device and give higher integration.
HTS magnet technology will promote the development of electron microscopes and HTS magnet research for future colliders.
Field mapping of the HTS magnetic lens (Image by IHEP)