THE MOST POWERFUL TRANSMISSION ELECTRON MICROSCOPE (TEM) has been built by a team led by Akira Tonomura at Hitachi's Advanced Research Lab. in collaboration with the Japan Science and Technology Corporation. In this kind of "field-emission" TEM, electrons are forced out of a cathode and accelerated with the use of a huge voltage and sent toward a sample. The voltage used was one million volts, and this produced a beam of electron waves with an intensity (more exactly, brightness) 4 times better than the best previous TEM (or 1000 times larger than conventional thermionic-emission TEMs).

The device is a marvel of engineering. The voltage has to be held steady at around a million volts with a stability of half a volt; while the electron source must be steady to within 0.5 nm. The new device can make out rows of atoms only half an angstrom apart (thus rivaling scanning tunneling microscopes) and can even take pictures fast enough, 60 per second (the same as TV), that movies have been made of fine gold particles changing their shapes.

Hitachi's Takeshi Kawasaki (tkawa@harl.hitachi.co.jp, 011-81-492-96-6111) says that the microscope will be useful for observing certain dynamic properties of condensed matter systems, one example being the movement of vortices in high-temperature superconductors. (Kawasaki et al., Applied Physics Letters, 6 March /pnu/2000/; Select Article.)