World's first terahertz microscope reveals quantum jiggle in electrons

MIT physicists have developed the world’s first terahertz microscope capable of directly imaging quantum-scale electron motion inside superconductors. Terahertz radiation, which oscillates at trillions of cycles per second, matches the natural vibration frequencies of atoms and electrons but traditionally suffers from a long wavelength that limits spatial resolution. The MIT team overcame this diffraction limit by using spintronic emitters—ultrathin metal layers excited by lasers to generate sharp terahertz pulses—and positioning samples extremely close to the emitter. This near-field approach compresses terahertz waves into microscopic spots, enabling nanoscale resolution without damaging delicate materials. Using this microscope, the researchers studied an atomically thin sample of the high-temperature superconductor bismuth strontium calcium copper oxide (BSCCO) cooled near absolute zero. They observed previously unseen collective oscillations of superconducting electrons, revealing a new mode of electron behavior predicted by theory but never directly visualized at terahertz frequencies before. Beyond superconductivity