One of the more intriguing aspects of covering optoelectronic research and its implementation is being able to monitor the progress of the different approaches researchers take to solve a problem or to achieve a goal. "There's more than one way to skin a cat," as the old saying goes. While this may seem like a statement of the obvious—after all, different solutions competing in the consumer market ultimately benefit us all in terms of better-designed products and lower prices—once in a while something comes along that highlights the value of keeping an open mind.
Two years ago, in a Laser Focus World special report on free-space optical communications we discussed optical data links, noting that, because of their higher bandwidth capacity, they would likely provide increasing competition for the well-established microwave links that are currently in use for line-of-sight communications. One of the problems with the optical links, however, is the detrimental effect of the weather (specifically fog and rain) on the laser beam carrying the data. It is perhaps ironic, then, that one of this month's features describes a system that actually combines microwave with free-space optical communications to establish a data link with the reliability required for commercial telecom applications (see p. 121)
Meanwhile, fiberoptic links are expected to achieve ever-increasing data rates, with transmission at 40 Gbit/s being the current goal. In this context, Raman optical amplifiers are of interest because they provide higher overall gain and a flatter gain profile across the wavelength-division multiplexing transmission spectrum as compared to the erbium-doped fiber amplifier. Engineers are investigating various approaches to Raman amplification and these are discussed in this month's Optical Networking feature (see p. 135).
VCs mine European opportunities
Optical communications has wrought major changes throughout the world of optoelectronics, not least of which is fostering the intense interest of venture capitalists (VC) hoping to find the next winning deal. VCs are apparently finding worthwhile deals across Europe, and changing the optoelectronic startup landscape from the Swiss Alps to the Highlands of Scotland (see p. 110). Even in the investment community, it seems that unfortunate feline can find many ways to lose its skin.P.S. This month, noting that Laser 2001 is taking place in Germany, we have included a special Optoelectronics World supplement that highlights the increasing importance of micromachining (see p. 179).