Month: February 2018

Enlarge / With the right type of processing, frosted glass can actually improve imaging. (credit: Steve K / Flickr)

It's probably not often that someone walks into your office and says, "I want you to make me a finely engineered device that makes everything worse." Yet that seems to be a solution to creating images of large areas that still retain lots of detail.

Normally, imaging systems are a product of extremely careful engineering. I've heard engineers talk about polishing lenses to an accuracy of a picometer (10^-12m) because that's what you need to do to reach some image requirements. In general, the more careful you are, the better the image. But recent developments have been going the other way. It turns out that we can make use of the randomness created by rough surfaces to obtain high-quality images.

Grind that glass

So imagine a sheet of glass: you shine laser light in, and laser light comes out. It's the most boring show on Earth. The next step is to roughen one face of the glass. After a bit of grinding (wear a mask), you have something like the translucent glass in your bathroom window. When you shine a laser light through that, what emerges is a mess of speckles and blur. We have successfully destroyed a laser beam.

Enlarge / Elon Musk speaks at a news conference at the National Press Club in Washington, DC, US, on Tuesday, April 5, 2011. (credit: Brendan Hoffman/Bloomberg via Getty Images)

Elon Musk appeared almost boyish back in April 2011 as he unveiled the Falcon Heavy rocket to a handful of reporters at the National Press Club. Still in his 30s, Musk had not yet become an international celebrity, and his efforts to transform the aerospace and automotive industries had not yet fully flowered. As such, this reveal lacked the splashy theatrics of Musk’s more recent rocket unveiling events.

Despite the pedestrian backdrop, this was quintessential Elon—sharing a vision, making bold promises, and sniping irreverently at his competition. “This is a rocket of truly huge scale,” Musk said during an unveiling of the rocket at the National Press Club in Washington, DC. “This is something America can be really proud of, a vehicle with twice the capability of the shuttle and Delta IV Heavy.”

The announcement came at a bleak moment for the US space industry. The space shuttle would make its final flight just three months later, leaving the United States without a way to get its astronauts in orbit. Launch costs for other US rockets were steadily rising. NASA’s exploration plans were muddled. America was going nowhere fast.

Enlarge / This is what this article is about. (credit: Knick Banas / Flickr)

Today, we are going to tackle a topic that every science journalist fears deeply: topological insulators. Fear not dear reader, once your head explodes, you'll feel nothing. Besides, these aren't just any topological insulators, they're topological insulator lasers, which definitely makes the pain worthwhile.

The question that should be foremost in your mind is: why would you combine the least-easily explained concept in physics with something so cool as lasers? And the answer is because it makes for a pretty good laser.

Before we get to how a topological insulator can improve a laser, let's take a look at what makes a laser so difficult.