Researchers from the Peking University in Beijing and Zhejiang University in Hangzhou have published the outcome of their research on a single-nanowire laser, which operates in a single mode, in Nano Letters issue.
Limin Tong, a researcher from the Zhejiang University, stated that unlike other single-nanowire lasers, the one mentioned in their study is single-mode and could prove useful for practical purposes
With a wavelength of around 738 nm, the nanowire, employed in making the breakthrough laser, is between 50 and 75 nm in length and 200 nm in diameter.
After experimenting with bending nanowires in various ways, the desired nanowire was achieved after a looped nanowire was excited with a pulsed laser. Since the looped nanowires doubled as loop mirrors, they reduced the lasing threshold and increased the wire’s reflectivity. The low threshold and high reflectivity generated a lasing cavity in the nanowire.
The researchers were also able to tune the wavelength of the laser by adjusting the loop size using fiber probes. Study showed that when the loop size was reduced, a reduction in the lasing cavity’s optical path caused a change in the wavelength.
With low lasing threshold and greater mode quality, the single-nanowire laser could open new avenues for sensible and realistic applications of lasers.
Tong also added that the nanowire laser developed by the researchers offers a single-mode laser output in a smaller footprint than other nanowire lasers, enabling its application in optical sensing and optical data processing circuits.
Source: http://www.zju.edu.cn/