| 1. |
- Dai, Daoxin, et al.
(författare)
-
Gain enhancement in a hybrid plasmonic nano-waveguide with a low-index or high-index gain medium
- 2011
-
Ingår i: Optics Express. - 1094-4087. ; 19:14, s. 12925-12936
-
Tidskriftsartikel (refereegranskat)abstract
- A theoretical investigation of a nano-scale hybrid plasmonic waveguide with a low-index as well as high-index gain medium is presented. The present hybrid plasmonic waveguide structure consists of a Si substrate, a buffer layer, a high-index dielectric rib, a low-index cladding, a low-index nano-slot, and an inverted metal rib. Due to the field enhancement in the nano-slot region, a gain enhancement is observed, i.e., the ratio partial derivative G/partial derivative g > 1, where g and G are the gains of the gain medium and the TM fundamental mode of the hybrid plasmonic waveguide, respectively. For a hybrid plasmonic waveguide with a core width of w(co) = 30nm and a slot height of h(slot) = 50nm, the intrinsic loss could be compensated when using a low-index medium with a moderate gain of 176dB/cm. When introducing the high-index gain medium for the hybrid plasmonic waveguide, a higher gain is obtained by choosing a wider core width. For the high-index gain case with h(slot) = 50nm and w(co) = 500nm, a gain of about 200dB/cm also suffices for the compensation of the intrinsic loss.
|
|
| 2. |
- Dai, Daoxin, et al.
(författare)
-
Integrated Silicon Photonic Nanocircuits and Technologies for Optical Interconnect and Optical Sensing
- 2012
-
Ingår i: OPTOELECTRONIC INTEGRATED CIRCUITS XIV. - : SPIE-INT SOC OPTICAL ENGINEERING. - 9780819489081
-
Konferensbidrag (refereegranskat)abstract
- Silicon-on-insulator (SOI) nanowires give a very promising way to realize ultrasmall photonic integrated devices because of the ability for ultrasharp bending as well as the CMOS compatibility. As a typical integrated-type (de) multiplexer, ultrasmall arrayed-waveguide gratings (AWG) are very attractive for many applications. We have developed several types of ultrasmall SOI-nanowire AWG with novel layouts. SOI nanowires also give a good platform for optical sensing with high sensitivity because of the enhanced evanescent field. We have developed SOI-nanowire-based optical sensors by using MZI (Mech-Zehnder interferometer)-coupled microrings and cascaded rings. We also note that the size of an SOI nanowire is still limited to the order of wavelength in each direction. In contrast, surface plasmon (SP) waveguides could provide a nano-scale waveguiding and confinement of light. However, the conventional nano-scale SP waveguides are usually quite lossy. We have proposed two types of novel hybrid plasmonic waveguides to achieve nano-scale optical confinement and low-loss light propagation. Due to the ultra-high optical confinement, sub-mu m-2 hybrid plasmonic devices (e. g., power splitters) are presented. It is also shown that hybrid plasmonic waveguide enables sub-mu m bending and thus sub-mu m resonator has been also demonstrated. The hybrid plasmonic waveguides offer a way to transfer both photonic and electronic signals along the same circuit, which is attractive for active components, e. g., tunable filters and optical modulators.
|
|
| 3. |
|
|
| 4. |
- Dai, Daoxin, et al.
(författare)
-
Silicon hybrid plasmonic submicron-donut resonator with pure dielectric access waveguides
- 2011
-
Ingår i: Optics Express. - 1094-4087. ; 19:24, s. 23671-23682
-
Tidskriftsartikel (refereegranskat)abstract
- Characteristic analyses are given for a bent silicon hybrid plasmonic waveguide, which has the ability of submicron bending (e.g., R = 500nm) even when operating at the infrared wavelength range (1.2 mu m similar to 2 mu m). A silicon hybrid plasmonic submicron-donut resonator is then presented by utilizing the sharp-bending ability of the hybrid plasmonic waveguide. In order to enable long-distance optical interconnects, a pure dielectric access waveguide is introduced for the present hybrid plasmonic submicron-donut resonator by utilizing the evanescent coupling between this pure dielectric waveguide and the submicron hybrid plasmonic resonator. Since the hybrid plasmonic waveguide has a relatively low intrinsic loss, the theoretical intrinsic Q-value is up to 2000 even when the bending radius is reduced to 800nm. By using a three-dimensional finite-difference time-domain (FDTD) method, the spectral response of hybrid plasmonic submicron-donut resonators with a bending radius of 800nm is simulated. The critical coupling of the resonance at around 1423nm is achieved by choosing a 80nm-wide gap between the access waveguide and the resonator. The corresponding loaded Q-value of the submicron-donut resonator is about 220.
|
|
| 5. |
- Dai, Daoxin, et al.
(författare)
-
Silicon Multimode Photonic Integrated Devices For On-Chip Mode-Division-Multiplexed Optical Interconnects
- 2013
-
Ingår i: Progress In Electromagnetics Research. - 1070-4698 .- 1559-8985. ; 143, s. 773-819
-
Tidskriftsartikel (refereegranskat)abstract
- Multimode spatial-division multiplexing (SDM) technology has attracted much attention for its potential to enhance the capacity of an optical-interconnect link with a single wavelength carrier. For a mode-multiplexed optical-interconnect link, the functional elements are quite different from the conventional ones as multiple modes are involved. In this paper we give a review and discussion on multimode photonic integrated devices for mode-multiplexed optical-interconnects. Light propagation and mode conversion in tapered waveguides as well as bent waveguides are discussed first. Recent progress on mode converter-(de)multiplexers is then reviewed. The demands of some functional devices used for mode-multiplexed optical-interconnects are also discussed. In particular, the fabrication tolerance is analyzed in detail for our hybrid demultiplexer, which enables mode-/polarization-division-(de)multiplexing simultaneously.
|
|
| 6. |
- Dai, Daoxin, et al.
(författare)
-
Ultracompact silicon nanowire circuits for optical communication and optical sensing
- 2011
-
Ingår i: 2011 IEEE Winter Topical. - 9781424484287 ; , s. 25-26
-
Konferensbidrag (refereegranskat)abstract
- By utilizing Si nanowires, ultracompact photonic integrated circuits are realized. Some Si hybrid plasmonic waveguides are also introduced for subwavelength optical confinement and low loss propagation. We review our recent work on Si nanophotonic integrated circuits and their applications.
|
|
| 7. |
- Guan, Xiaowei, et al.
(författare)
-
Ultracompact and broadband polarization beam splitter utilizing the evanescent coupling between a hybrid plasmonic waveguide and a silicon nanowire
- 2013
-
Ingår i: Optics Letters. - 0146-9592 .- 1539-4794. ; 38:16, s. 3005-3008
-
Tidskriftsartikel (refereegranskat)abstract
- An ultracompact polarization beam splitter (PBS) is proposed based on an asymmetrical directional coupler consisting of a silicon hybrid plasmonic waveguide (HPW) and a silicon nanowire. The widths of the two coupling waveguides are chosen so that the phase-matching condition is satisfied for TE polarization only while the phase mismatch is significant for TM polarization. A sharply bent silicon HPW is connected at the thru port to play the role of polarizer by utilizing its polarization-dependent loss. With the present principle, the designed PBS has a footprint as small as only similar to 1.9 mu m x 3.7 mu m, which is the shortest PBS reported until now, even when large waveguide dimensions (e. g., the waveguide widths w(1,2) = similar to 300 nm and the gap width w(gap) = similar to 200 nm) are chosen to simplify the fabrication process. The numerical simulations show that the designed PBS has a very broad band (similar to 120 nm) with an extinction ratio >12 dB and a large fabrication tolerance to allow a waveguide width variation of similar to 30 nm.
|
|
| 8. |
- Guan, Xiaowei, et al.
(författare)
-
Ultrasmall Directional Coupler and Disk-resonantor Based on Nano-scale Silicon Hybrid Plasmonic Waveguides
- 2012
-
Ingår i: 2012 Asia Communications And Photonics Conference (ACP). - Washington, D.C. : OSA. - 9781467362740 ; , s. AS2H.4-
-
Konferensbidrag (refereegranskat)abstract
- Nanophotonic integrated devices based on nano-scale silicon hybrid plasmonic waveguides have been demonstrated experimentally, including directional couplers and disk-resonators. The temperature-dependence of the hybrid plasmonic disk-resonators is also characterized.
|
|
| 9. |
- Jiao, Yuqing, et al.
(författare)
-
Accurate and efficient simulation for silicon-nanowire-based multimode interference couplers with a 3D finite-element mode-propagation analysis
- 2010
-
Ingår i: Journal of the Optical Society of America. B, Optical physics. - : Optical Society of American (OSA). - 0740-3224 .- 1520-8540. ; 27:9, s. 1813-1818
-
Tidskriftsartikel (refereegranskat)abstract
- A three-dimensional (3D) finite-element mode-propagation analysis is presented to give an accurate and efficient simulation for silicon-nanowire- based multimode interference (MMI) couplers. For the presented numerical method, a finite-element method mode solver is used to calculate the mode profiles and the propagation constants in a multimode section. The comparison between the presented method and some other numerical methods [e.g., finite-difference time-domain (FDTD) method, beam propagation methods, etc.] is also shown. It is shown that the presented numerical method gives simulation results very close to those from the 3D FDTD (with a deviation less than 1%). Therefore, it is very convenient for the design of Si-nanowire-based MMI couplers.
|
|
| 10. |
- Lou, Fei, et al.
(författare)
-
Design and analysis of ultra-compact EO polymer modulators based on hybrid plasmonic microring resonators
- 2013
-
Ingår i: Optics Express. - 1094-4087. ; 21:17, s. 20041-20051
-
Tidskriftsartikel (refereegranskat)abstract
- Ultra-compact EO polymer modulators based on hybrid plasmonic microring resonators are proposed, simulated and analyzed. Comparing with Si slot microring modulator, hybrid plasmonic microring modulator shows about 6-times enhancement of the figure of merit when the bending radius is around 510 nm, due to its much larger intrinsic quality factor in sub-micron radius range. Influences of the EO polymer height and Si height on the device's performance are analyzed and optimal design is given. When operating with a bias of 3.6V, the proposed device has optical modulation amplitude of 0.8 and insertion loss of about 1 dB. The estimated power consumption is about 5 fJ/bit at 100 GHz.
|
|
