Plasmonic lasers: On the fast track

The dependence of the output power on the delay indicated that the generated pulse length was less than a picosecond, which suggested an extremely high direct-modulation rate. Moreover, finer interferometric measurements of the spectral composition of the radiation allowed the authors to establish that the generated pulse was even shorter; on a subpicosecond scale. Thus, this spaser has more than a terahertz in the direct modulation bandwidth — a record-setting achievement.

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Nanosphere lithography for device fabrication

Nanosphere lithography (NSL), originally termed ‘ natural lithography’ by its inventors,1 is becoming a widespread bottom-up technique to pattern solid surfaces at the sub-micrometer and nanoscales. Groups such as Van Duyne’s2 at Northwestern University and others3 undertook pioneering work on NSL in the 1990s and early this decade, and a growing number of research laboratories around the globe now use the technique in many scientific disciplines. The approach has applications in various materials systems, is fast and scalable to large surface areas, and is inexpensive in terms of equipment and operation. Some variants of the technique have reached a high level of maturity and control. Therefore, it is likely that it will soon be used in device fabrication.

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UT Austin Engineers Build First Nonreciprocal Acoustic Circulator: A One-Way Sound Device

AUSTIN, Texas — A team of researchers at The University of Texas at Austin’s Cockrell School of Engineering has built the first-ever circulator for sound. The team’s experiments successfully prove that the fundamental symmetry with which acoustic waves travel through air between two points in space (“if you can hear, you can also be heard”) can be broken by a compact and simple device.

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