2015 Fiscal Year Annual Research Report
ハイブリッド型プラズモニックキャビティ－チャンネル構造によるサブ波長ナノレーザー
| Project/Area Number |
15F15359
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
J・J Delaunay 東京大学, 工学(系)研究科(研究院), 准教授 (80376516)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HO YA-LUN 東京大学, 工学(系)研究科(研究院), 外国人特別研究員
|
|---|
| Project Period (FY) |
2015-11-09 – 2018-03-31
|
| Keywords | Plasmonics / nanostructure |
|---|
| Outline of Annual Research Achievements |
This proposal is related to the demonstration of nanolasers using the property of plasmonic nanofin structure developed in our laboratory. We show that nanofins can be used to strongly confine light in new sub-wavelength structures and design a new structure consisting of a subwavelength channel made of the lasing material which is embedded between plasmonic nanofin structures. The nanofins embedding the channel are plasmonic resonant structures, which are used to “focus” light in the channel. All the structures used in this study are sub-wavelength and exhibit properties governed by plasmonic resonances, that is, the structure is not diffraction limited and enables the fabrication of nanolasers. Due to the efficient light confinement provided by the sub-wavelength nanofins plasmonic structure, a very low lasing threshold should be obtained (efficient use of energy) and a nanosize light source should be achieved (imaging with resolution below the diffraction limit). Finally, the proposed structure can be applied to any wavelength, so nanolasers for telecommunication (1.55 um) integrated on a wafer is also possible, thus offering a means to integrate optical nano-circuit directly on CMOS technology.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
The first half year of the project was dedicated to the optimization by simulation of the proposed structure as well as to the establishment of a fabrication technique. Hereafter, we report the progress made in the fabrication technique and the characterization of the fabricated structure. The nanochannel structure was fabricated with silicon nanochannel and gold nanofin U-cavity. The strong light confinement is quantified using the full width at half maximum (FWHM) of the resonance bandwidth and the ratio between the full height and full width at half-maximum (FH/FWHM). The resonance is obtained at a wavelength λ = 1105 nm and the bandwidth of the resonance has a FWHM of 9 nm. The FWHM of the resonance from nanochannel structure, among the smallest for plasmonic nanostructured devices in the near-infrared region, is evidence of the superior light concentration properties of the nanochannel structure. Moreover, the large reflectance modulation at the resonances is another major merit of the nanochannel structure. The reflectance modulation, quantified by the FH/FWHM, is as large as 0.048 nm^-1. This value is the largest among the reported nanostructured devices having similar resonance wavelengths.
|
| Strategy for Future Research Activity |
After establishing the fabrication technique using a technological material (silicon), we focus on materials used for lasing. Optimization of the structure by simulation for different materials will be performed and the fabrication technique adapted so that the new materials can be used in our fabrication technique. Particularly, we focus on the accurate simulation of the lasing wavelength and excitation wavelength using the rigorous coupled-wave analysis technique, finite-difference time-domain method, and finite element method. Also, lasing material deposition abd etching will be investigated.
|
Research Products
(1 results)
