special issue

The laser at 50: The early yearsphysicsworld.comHughes Research Laboratoriesfrom an unknown working for an aircraft company. Thebiggest problem, however, was that Mai man’s detailedscientific results were not available for scrutiny whenthe press conference was held. Worse, the Nature paper– when it was finally published on 6 August – was sobrief that it failed to convince his critics.Despite the uncertainty, Hughes’ press conferenceinfused the laser research community with new vigourand new funding. Scientists around the world returnedto their work with fresh conviction that it was actuallypossible to make a laser. In fact, the concept and designof Maiman’s laser proved so simple that it was only amatter of weeks before his results had been reproducedby several other researchers – most prominently those atBell Labs, who demonstrated a pencil beam from theirruby device on 1 August 1960. Taking their cue from thepublicity photograph showing “not the first” laser (seeimage left), the Bell Labs researchers used a 5 cm-longruby rod with an identical model of strobe lamp.By then, Maiman had also observed a pencil beam,thanks to three new ruby crystals that had been speciallygrown to the dimensions he required (the ruby inthe first laser, by contrast, had been cut from a largerboule). On the day the new crystals arrived, 20 July1960, Maiman inserted them into his device andobserved sharp threshold behaviour and a bright spoton the wall.Better than thereal thing?The photographissued at the 7 July1960 Hughes pressconference showingMaiman with a laterprototype laser – notthe first one– ledto melodramaticnewspaper headlinesand confusion amongother researchers.26sent it to Nature, where it was accepted (187 493). Be -fore it could be published, however, Hughes decided tohold a press conference. As a scientist, Maiman wantedto publish first, but Hughes was becoming nervous: theBell Labs groups might be really close, and there wouldbe no prize for second place.The Hughes public-relations machine swung intoaction ahead of the press conference, which it hadscheduled for 7 July 1960. The photographer hired totake the shots was not impressed by the first laser – itwas too small (see image on page 23). Looking aroundthe lab, he picked up a later prototype with a mediumsizedflash lamp and 5 cm-long ruby rod, telling Mai -man to “Hold this in front of your face and I know thiswill be picked up by every news outlet, but if we printthis, this first laser, it won’t go anywhere.” The photo -grapher was right. The day after the press conferenceall the major newspapers carried the photograph –along with, in one case, the melodramatic headline“LA man discovers science-fiction death ray”.Within the academic community, though, there was acertain amount of scepticism and confusion about whatMaiman had achieved. The optical quality of the crystalin his first laser was poor and so he had not ob servedthe characteristic “pencil beam”. Instead, his early re -sults were based on sensitive spectroscopic measurements.Maiman also faced some degree of prejudice:people expected the advance to come from Bell Labsor one of the other well-funded research efforts, notStill controversialIn the years that followed, Bell Labs researchersachieved many laser “firsts”, including the first gaslaser, which Javan and co-workers demonstrated successfullyin December 1960. Other successes includedthe first continuously operating ruby laser, made byWillard Boyle and Donald Nelson in 1961; the first carbon-dioxidelaser, invented by Kumar Patel in 1964;and a string of other innovations, including refinementsto the now-ubiquitous semiconductor diode laser.Maiman, for his part, left Hughes in 1961 to join aventure-capital-funded start-up called Quanatron,where he was in charge of laser activities. The followingyear Union Carbide provided the funds to set up his labas an independent business. Thus Maiman becamepresident of the newly formed Korad Corporation,which invented the Q-switched laser and became a supplierof the highest power lasers in the industry.Over the laser’s 50-year history, Maiman’s place asinventor of the laser has sometimes been acknow -ledged. In 1984 he was inducted into the National In -ventors Hall of Fame – meeting Kathleen, who becamehis second wife, on the flight home afterwards. Mostsignificantly, in 1987 he was awarded the Japan Prize,which is often considered the Eastern equivalent ofthe Nobel.But at other times, Maiman felt his role was downplayed.It was Townes who shared the 1964 Nobel Prizefor Physics with two Russian theorists, Nicolay Basovand Aleksandr Prokhorov, for “contributions to fundamentalwork in quantum electronics leading to thedevelopment of the maser–laser principle”. And in1998, Bell Labs honoured Townes’ work again with amajor celebration to mark “the 40th anniversary of thelaser” – a reference to the 1958 “optical maser” paper,rather than to the invention of a working device twoPhysics World May 2010