Quantum Leap

Each year, the size of transistors shrinks, thereby improving performance. Yet transistors must be big enough to allow electrons to pass through. Preparing for an inevitable impasse, Toshiba recently demonstrated a transistor that can turn on and off based on the movement of a single electron. Unlike other experimental quantum-level transistors, the device can operate at room temperature. It’s also the first successful hybrid circuit, mixing single-electron transistors with traditional metal-oxide transistors, which are required to boost the weak quantum-level signal. Chips based on the circuit should offer blazing performance and low power consumption. Before building a full-fledged processor, researchers face challenges such as finding a way to protect the chip from the disrupting effects of stray electromagnetic fields, electrical discharges and physical movement. Hybrid chips should be available commercially by 2010. -C. Conti