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  3. The word "laser" was coined as an acronym for Light Amplification by the Sti

The word "laser" was coined as an acronym for Light Amplification by the Sti

游客2024-06-10  30
问题     The word "laser" was coined as an acronym for Light Amplification by the Stimulated Emission of Radiation. Ordinary light, from the Sun of a light bulb, is emitted spontaneously, when atoms or molecules get rid of excess energy by themselves, without any outside intervention. Stimulated emission is different because it occurs when an atom of molecules holding onto excess energy has been stimulated to emit it as light.
    Albert Einstein was the first to suggest the existence of stimulated emission in a paper published in 1917. However, for many years physicists thought that atoms and molecules always were much more likely to emit light spontaneously and that stimulated emission thus always would be much weaker. It was not until after the Second World War that physicists began trying to make stimulated emission dominate. They sought ways by which one atom or molecule could stimulate many others to emit light, amplifying it to much higher powers.
    The first to succeed was Charles H. Townes, then at Columbia University in New York. Instead of working with light, however, he worked with microwaves, which have a much longer wavelength, and built a device he called a "maser", for Microwave Amplification by the Stimulated Emission of Radiation. Although he thought of the key idea in 1951, the first maser was not completed until a couple of years later. Before long, many other physicists were building masers and trying to discover how to produce stimulated emission at even shorter wavelengths.
    The key concepts emerged about 1957. Townes and Arthur Schawlow, at Bell Telephone Laboratories, wrote a long paper outlining the conditions needed to amplify stimulated emission of visible light waves. At about the same time, similar ideas crystallized in the mind of Gordon Gould, then a 37-year-old graduate student at Columbia, who wrote them down in a series of notebooks. Townes and Schawlow published their ideas in a scientific journal, Physical Review Letter, but Gould fried a patent application. Three decades later, people still argue about who deserves the credit for the concept of the laser. [br] Why do people still argue about who deserves the credit for the concept of the laser?
选项 A、The researchers’ notebooks were lost.
B、Several people were developing the idea at the same time.
C、No one claimed credit for the development until recently.
D、The research work is still incomplete.
答案 B
解析 事实细节题。最后一段讲到Townes, Schawlow及Gould等人几乎同时构思出了激光产生的条件，前两人在一本科学杂志上发表了自己的观点，而第三个人则注册了专利使用权，因此人们对荣誉应归属谁还争执不休，故B“有好几个人同时提出了那个想法”为最佳选项。A为“因为研究人员的记录本丢失了”和D为“该研究工作尚未完成”在文章中并没有提到：C为“直到最近无人获得荣誉”，这是对文章最后一句话断章取义的说法，因此也是错误的。
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