Background The 1970 demonstration of the first room-temperature diode laser crowned years of scientific and technological research developments involving optical semiconductors. These accomplishments parallel, but lag, the microelectronics revolution that started with the
transistor, first demonstrated in 1947 (leading to the displacement of
vacuum tube electronics in the marketplace). Although the
laser had already been invented by
Charles Hard Townes and
Arthur Leonard Schawlow, separately by
Gordon Gould, and separately in the Soviet Union by Aleksandr Prokhorov, there was no practical laser "
chip" which would make the laser a commodity, one that today is displacing more inefficient lasers (those based on
gas discharge or
flashlamp designs) in the consumer, industrial, medical, and government marketplaces. Shortly after the accomplishments attributed to Townes and Schawlow, the possibility of lasing in a semiconductor device was recognized. The key major accomplishment was the 1962 observation of nearly 100% internal efficiency in the conversion of electron-hole pairs to photons in GaAs semiconductor devices at MIT
Lincoln Laboratory,
RCA Laboratories, and
Texas Instruments, Inc., shortly thereafter followed by the demonstration of the first diode laser by
General Electric and
IBM. The new semiconductor laser devices operated only at cryogenic temperatures (typically that of
liquid nitrogen, that is, at 77K or –196 °C). For practical use, it would be necessary to demonstrate diode laser action, continuous-wave, at room temperature.
Invention of room-temperature diode laser The invention of the first room-temperature diode laser in the Soviet Union occurred during a climate of intense
Cold War competition and secrecy, albeit with sporadic scientific contacts at international conferences and during politically sanctioned international visits. The question of primacy of the invention was debated over the years. Today, however, semiconductor laser scientists agree that the key design concept that enabled the room-temperature diode laser, namely the double-heterostructure design, was invented in the Soviet Union in 1964 by Rudolf F. Kazarinov and Zhores Alferov, as recorded in a Russian patent application filed that year. For that invention and several other seminal contributions to the semiconductor lasers Rudolf F. Kazarinov won the 1998 Quantum Electronics Award of the IEEE Photonics Society (see below at References). While the Nobel Prize committee satisfied itself that the Russian team including Dmitri Z. Garbuzov, led by Zhores Alferov, reached continuous-wave room-temperature lasing before the competing team of Hayashi and Panish at Bell Labs, there continues to be discussion on this point, and the matter may never perfectly be resolved. Today, as a result of the accomplishments of Garbuzov and other scientists, diode lasers continue to transform the laser into a widely available engineered component. Laser chips are incorporated in many products that today are taken for granted, such as CDs, DVDs, laser printers, and fiberoptic communications. Other devices relying on semiconductor laser chip technology include illumination, ranging, and spectroscopic sensing systems of many types, and laser welding, cutting, and machining tools such as those now widely adopted by automobile manufacturers. In addition, the same principles first developed by Garbuzov and Alferov underlie the ongoing revolution in
gallium nitride-based solid-state lighting with high-quality high-efficiency phosphor-LED luminaires now available to consumers at affordable prices. == Later years in Russia ==