Ted Maiman and the world's first laser

Ted Maiman was born in Los Angeles, California, in 1927. His father was an electronics engineer and inventor, who worked for several years at Bell Labs during the war. The elder Maiman inspired his son with a love of electronics, and by the time the younger Maiman was 12 he had a job repairing valve devices. By the time he was 14, he was running the company's shop.

Maiman attended the University of Colorado, receiving a B.S. in engineering physics in 1949. He then set his sights on the Stanford University physics department for graduate work, but was initially rejected. He eventually got into Stanford, he was accepted by the electronics engineering department.

At Stanford, Maiman did graduate work under Nobel Laureate Willis Lamb. While conducting the experiment he learned a great deal about optical instrumentation, which was very appropriate to his later work on the laser.

Maiman graduated with a Ph D in physics from Stanford in 1955.

In 1958, Bell Labs' Schawlow and Townes had predicted the operation of an optical laser. In their paper, they suggested that one way to do it was using alkali vapors. They applied for, and were granted, a patent. But a working laser had yet to be built.

Meanwhile Maiman was now working at Hughes Research, which was one of the many labs involved in the race to implement the laser.

 

At Hughes, Maiman found himself encountering a number of obstacles. He was under-funded, working with a budget of $50,000, which included his salary, his assistants' salaries, and equipment. Worst of all, the most important scientists of the day were scoffing at him for continuing to investigate ruby, which had been ruled out as a lasing material. It was measured that the fluorescence quantum efficiency of ruby was about 1 percent.

Maiman began investigating other materials, but having found no alternative prospects, he returned to ruby to try to understand why it was so inefficient. He felt that if he could understand what was causing the inefficiency, he could then work with crystal experts to identify an appropriate material. He measured the quantum efficiency again, and came up with a figure of about 75 percent! Ruby was again a laser candidate.

At this time, nearly all the scientists in the major labs were trying to make a continuous laser. Few were considering the possibility that a pulsed laser might be easier to build. Maiman did not accept this idea.

At about that time he came across an article on photographic strobe lamps, and discovered that their brightness temperature was about 8000 or 9000 K. The continuous dc arc lamp he had looked at had a brightness temperature of about 4000 K. He checked his calculations carefully (calculators and desktop computers were still science fiction in 1960). An innovative optical pump and probe and simultaneous GHz resonant cavity experiment convinced him the strobe lamp could make optical gain a reality.

By surrounding the ruby rod with the lamp and using an external collector, Maiman was able to achieve a reasonable amount of pumping efficiency. He obtained a ruby rod from Union Carbide. It was a unique request, and took the company five or six months to prepare.

In 1960, there were no coating surfaces for laser mirrors, and multilayer coatings were only at the disposal of the largest labs that could afford the technology. But Maiman knew about silvering ruby from his maser days, and he used the same technique to silver the ends of this rod.

Maiman's rigorous investigation was paid off when, on 16 May 1960, the laser made the historic leap from theory to reality.


 

 

 
 






Дата добавления: 2016-07-18; просмотров: 1115; ЗАКАЗАТЬ НАПИСАНИЕ РАБОТЫ


Поиск по сайту:

Воспользовавшись поиском можно найти нужную информацию на сайте.

Поделитесь с друзьями:

Считаете данную информацию полезной, тогда расскажите друзьям в соц. сетях.
Poznayka.org - Познайка.Орг - 2016-2021 год. Материал предоставляется для ознакомительных и учебных целей. | Обратная связь
Генерация страницы за: 0.012 сек.