Femtosecond laser pulses can be used to induce ultrafast changes of the magnetization in magnetic materials. The mechanism of ultrafast quenching of the magnetization triggered by a femtosecond laser pulse is currently still hotly debated. Despite the large amount of work devoted to the characterization of femtosecond demagnetization in various metallic systems, so far no consensus over the sub-picosecond demagnetization mechanisms has emerged. One of the unsolved questions is that of (...)
Transforming electrical current into light is critical for technologies such as telecommunications and displays. In Physical Review Letters, researchers report luminescence from a single polymer molecule, representing the smallest possible organic light-emitting diode (OLED) device.