Scientists at Columbia Engineering have done the impossible and created lasers that fit on your fingertip, producing pure colors of light from near-ultraviolet to near-infrared. These tiny lasers can be precisely tuned and are as fast as lightning, reaching speeds of up to 267 petahertz per second. This makes them perfect for applications such as quantum optics.

The team is the first to demonstrate chip-scale, narrow-linewidth, and tunable lasers for colors of light below red, including green, cyan, blue, and violet. This is a big deal because, until now, the only way to have a laser light show was to rent a big, bulky and expensive machine. But now, you can have your own personal laser light show right on your finger. Who needs a full-sized laser show when you have a fingertip laser?

The researchers had to overcome some significant challenges to achieve this breakthrough, such as the issue of coupling and propagation loss. But with the help of Fabry-Perot (FP) diodes, indium phosphide (InP) and a technique called "resonant coupling", they were able to create these tiny yet powerful lasers. (read more here)

The resulting lasers not only small and efficient, but also inexpensive, which makes them a practical solution for a wide range of applications. This research has the potential to revolutionize the way we use light in various fields such as quantum optics, displays, and bioimaging, and many more. And also to make you the coolest kid in the block with your finger laser pointer.

That Crazy Genius Professor At Your Fingertips

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🔋 The Next Big Thing in Energy Storage

Improved NA-S Batteries with Reduced Costs and Increased Storage Capacity

Well, well, well, it looks like the battery world just got a whole lot more interesting! A team of Chinese and Australian scientists at the University of Sydney have potentially revolutionized the battery game with their new sodium-sulfur (Na-S) batteries. According to them, these batteries will significantly reduce costs and improve storage capacity by as much as 4 times more than the standard lithium-ion battery.

Now, you might be thinking, "Na-S batteries? Haven't we heard that before?" And yes, my dear reader, we have. But in the past, these batteries were known for their less-than-stellar performance due to their high operating temperature requirements of 300-350°C. This significantly increases operating and maintenance costs and also increases safety risks, as the molten electrodes become more chemically reactive. But, these scientists have cracked the code and found a way to make the batteries perform at room temperature, without the need for a pricey heating system. By using a simple pyrolysis process and carbon-based electrodes, the reactivity of sulfur and the reversibility of reactions between sulfur and sodium were significantly improved. (Read more here)

So, not only are these batteries cheaper to produce and maintain, they also have the potential to store 4 times more power than the current lithium-ion batteries. As the research director, Shenlong Zhao, put it: "Our sodium battery has the potential to drastically reduce production costs and provide four times more storage capacity". Talk about a game-changer! The whole green transitions will become a whole lot easier with these new batteries in the mix. So, hold on to your lithium-ions, folks, because the battery game is about to get shaken up!