Physics and Astronomy
Research Advisor: Thomas Killian
What happens when it gets cold? And by cold, I mean about -459°F cold. At low enough temperatures, matter behaves in fundamentally different ways. By studying atoms at just fractions above absolute zero, Joshua Hill of Dr. Thomas Killian’s research group is shedding light on basic laws of nature. Joshua believes his research will allow physicists to model the behavior of strange materials, and unlock the secret of superconductors.
Absolute zero is the lowest limit of the thermodynamic temperature scale. It does not occur naturally, and advanced techniques are required to get near it. “In my lab, we use lasers to trap, cool, and manipulate gaseous samples of the element Strontium. For a laser of the appropriate frequency, we scatter photons off of the atoms only when the direction of the photon’s momentum opposes that of the atom’s movement. In this way, we can slow down the atom’s velocity, and cool them to small fractions above absolute zero.”
Although the atoms Joshua works with are too small to touch, his experiments are very hands-on. “We are a very hands-on experimental lab, and students build, maintain, and optimize much of our own equipment. The primary hardware most experimentalists in the field use are lasers, optics, vacuum chambers, and electronics. We also use custom circuits, radio-frequency electronics, and hundreds of mirrors and lenses to control these aspects of the beams.”
As someone who loves to build and create things, Joshua was first attracted to his field of study because of the wide array of equipment used in experiments. “It’s both exciting and daunting to be responsible for an entire room packed to the brim with equipment.”
To Joshua, physics is a field that has been interesting and challenging — but physics was not a path that he had in mind when he was younger. “I didn’t go to high school, but instead got a GED and worked my way through community college. I’ve had my share of jobs that were the opposite of the one I currently find myself in, and I’m grateful to be here.”
Outside of the lab, Joshua is active in the Graduate Student Association and have taken on the many different roles, including director, vice president, and parliamentarian. You can also find him as a bartender in Valhalla serving drinks. Refer to Joshua's website to learn more: jchill.rice.edu.