Looking at atoms is actually nothing new

In a basement below the University of Victoria, workers are putting the finishing touches on a $1.2 million “dead” room. Thick panels block out electromagnetic waves. Large fabric “socks” cover the room’s air-conditioning vents to block even the slightest draft. The room even stands on its foundation to shield it from infinitesimal vibrations elsewhere in the building.

It is in this room that scientists are preparing to install the most powerful microscope in human history. Known as the Scanning Transmission Electron Holography Microscope (STEHM), when it is operational it will be capable of zooming in to magnifications of about 40 trillionths of a meter — 2.5 million times smaller than the width of a sheet of paper.

The microscope is so sensitive that its accuracy could be affected by little more than a passing cloud. Its specimens will be so small that researchers will need a conventional electron microscope just to prepare them. But it is well worth the trouble. Once the machine is up and running, it will give researchers an unprecedented look into the subatomic universe.

Little is known about the characteristics of the subatomic world. Scientists have some knowledge of how waves and atoms behave in environments of only a few trillionths of a meter, but nobody has seen it firsthand. Using the STEHM, scientists can begin making detailed measurements of previously unknown sub-atomic characteristics. Those measurements, in turn, will be a valuable roadmap in designing nanotechnology.

The machine is the brainchild of long-time microscopy researcher Rodney Herring. About 10 years ago, while working as a microgravity scientist at the Canadian Space Agency, Mr. Herring hit upon the idea of assembling a world-class microscope by marrying together two microscopy technologies being developed in Japan and Germany. Numerous failed grant applications later, in 2007 he finally secured $4-million from the Canadian Foundation for Innovation and another $4 million from the British Columbia Knowledge Development Fund. Now, as the director of UVic’s newly-minted Advanced Microscopy Lab, he is laying the ground work for the STEHM.

Although the race to build ever-more-powerful microscopes isn’t as testosterone fuelled as, say, breaking the land-speed record, it is still a point of competition among scientists. “There is a real race, always, in science and technology,” says Mr. Herring.

Located at the end of a concrete stairwell, the Advanced Microscopy Lab is eerily insulated from the rest of the campus. Due to the sensitivity of their equipment, advanced microscopy researchers spend much of their career underground. Lab manager Elaine Humphrey spent years at an electron microscopy lab at the University of British Columbia and describes having been oblivious to rain, windstorms and even earthquakes. Of course, it’s important to make sure your microscopy lab has full-spectrum lights. “In the winter, we go to work in the dark and then we go home in the dark — these keep us sane,” she says.

The STEHM is currently in Germany being fitted with its last set of correctors. After making its way across the Atlantic and through the Panama Canal, it will be un-crated, gingerly lowered into the Advanced Microscopy Lab through a hole in the ceiling and manoeuvred into place using a ceiling-mounted crane. The microscope itself essentially resembles a massive metal cylinder encased in wires. Researchers will mount a small stepladder and insert their specimen through a tiny airlock. Then, they’ll seal the room with a pair of heavy doors and operate the microscope remotely from an adjoining room.

The whole process has a certain science fiction quality to it. When she was based in Vancouver, Ms. Humphrey says she often got calls from film producers looking for futuristic-looking microscopy equipment to decorate a movie set.

Some of the STEHM’s features do indeed seem pulled from the pages of a fantasy novel. It is the world’s first microscope to be fitted with an “electron vortex beam,” a beam of electrons that functions like a pair of atomic tweezers, allowing researchers to manoeuvre individual atoms in a specimen. “It will be like having hands down there – it’s the newest, hottest thing,” says Mr. Herring.

Conventional light microscopes — such as those used in a high school science class — are unable to get even close to the magnifications reachers by electron microscopes like the STEHM. Light waves are much too big and clunky to focus in on the atomic level. Electron microscopes get around this by replacing light waves with beams of electrons. The STEHM will use a high-powered electron gun to fire electrons through a specimen and then buil an image based on the electrons that pass through that specimen. It’s similar to shining a light through a photographic slide.

Currently, the title for world’s most powerful electron microscope belongs to a machine housed at the Lawrence Berkeley National Laboratory in California. Operational since 2008, the $25-million Berkeley microscope has published stunningly clear images of gold and carbon atoms arranged in neat, honeycomb structures.

Looking at atoms is actually nothing new. In 1970, Albert Crewe, a physicist at the University of Chicago, used a redesigned electron microscope to capture history’s first images of individual atoms. The problem was; the pictures were blurry. Once you zoomed in to the atomic level, miniscule aberrations in the structure and direction of the electron beam begin causing distortions in the image. It was akin to having a world-class telescope, but not having the right eyeglass prescription. “There were 30 years where things didn’t change much,” says Mr. Herring. Then, around the year 2000, microscope manufacturers broke the deadlock by introducing “correctors” that could fine-tune the characteristics of an electron beam. Correctors are now standard on the world’s top microscopes, but what makes the UVic machine so powerful is that it features two new types of this technology.