Alfred | Kastler

Kastler’s groundbreaking technique, developed alongside Jean Brossel, is known as "optical pumping."

In the mid-20th century, physicists could observe atoms, but they couldn't easily control their internal states. Enter Alfred Kastler, a French physicist whose ingenious methods of using light to manipulate atomic energy levels earned him the 1966 Nobel Prize in Physics. Kastler didn't just study light; he taught it to reorganize the structure of matter. alfred kastler

Production of 203Pb from enriched 205Tl using deuteron beams Production of 203Pb from enriched 205Tl using deuteron

Kastler’s work laid the groundwork for modern atomic clocks, the most precise timekeeping devices known, which are essential for GPS technology. Kastler's light acted as the teacher, getting all

Kastler discovered that by irradiating atoms with specially polarized light, he could push electrons into higher energy levels, effectively "pumping" them into a specific, ordered state.

Imagine atoms as unruly students in a classroom. Kastler's light acted as the teacher, getting all students to look in the same direction, making them easier to teach (or in this case, measure). Legacy and Impact