Photoelastic Effect in Silicon Ring Resonators

Amemiya, Yoshihito; Tanushi, Yuichiro; Tokunaga, Tomochika; Yokoyama, Shiyoshi

doi:10.1143/jjap.47.2910

Cited by 15 publications

(14 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the reversible regime, it was approximated that the strain of the membrane increases by 1.5 × 10 −4 compared to its annealed state. Interestingly, the light‐induced increase of strain can be related to the increased effective refractive index as consistently observed in our experiments, since the increase of strain is reported to increase the refractive index . It was reported that the strain increase by applied external force in the order of 10 −4 results in 0.1 nm red‐shift for c‐Si‐based MRR .…”

Section: Resultssupporting

confidence: 86%

“…Therefore, we cannot make a direct comparison between the refractive index change observed for the MRR device or AR coating and the membrane strain change. However, the demonstrated results present a reasonable similarity between strain change and refractive index change, that is, a device performance shift under applied strain, as has been reported elsewhere …”

Section: Resultssupporting

confidence: 85%

See 1 more Smart Citation

Metastable Refractive Index Manipulation in Hydrogenated Amorphous Silicon for Reconfigurable Photonics

Mohammed

Melskens

Pagliano

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

Hydrogenated amorphous silicon (a‐Si:H) is known for exhibiting light‐induced metastable properties that are reversible upon annealing. While these are commonly associated with the well‐known deleterious Staebler–Wronski effect in the field of thin‐film silicon solar cells, the associated changes in optical properties have not been well studied. Emerging reconfigurable photonic devices and applications can benefit from metastable optical properties where two states of the material are reversibly accessible without the need for continuous stimulation. The study demonstrates a light‐induced 0.3% increase of the metastable refractive index of a‐Si:H that is reversed upon annealing over several cycles using a highly sensitive Fabry–Pérot interferometric technique. Utilizing this technique, a metastable optical switch based on a micro‐ring resonator is demonstrated with reversible distinct switching states separated by 0.3 nm between the light‐soaked and annealed states, a switching extinction exceeding 20 dB and an unchanged Q‐factor, suggesting no excess discernible optical loss. Furthermore, metastable strain changes in a‐Si:H‐based freestanding membrane structures are linked to the observed metastable optical properties and present a possible route to stable photonic devices. Our proof‐of‐concept demonstration showcases a‐Si:H‐based reconfigurable photonics that support multiple purpose photonic integrated circuits, reconfigurable metamaterials, and advanced optomechanical devices.

show abstract

Section: Resultssupporting

confidence: 86%

Section: Resultssupporting

confidence: 85%

Metastable Refractive Index Manipulation in Hydrogenated Amorphous Silicon for Reconfigurable Photonics

Mohammed

Melskens

Pagliano

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…Strong lateral confinement of the light due to the high refractive index contrast of SOI waveguides (Δn ≈ 2) allows for small device footprint, but also comes with high sensitivity to the exact behavior of the modes in the waveguide, e.g., strong modal dispersion [7,8]. Amemiya et al [9] reported on the photoelastic effect in strained SOI ring resonators without, however, considering the modal effects, such as dispersion. In this Letter, we first derive a model explaining the effects that play a role when considering the influence of strain on photonic waveguides.…”

mentioning

confidence: 99%

Characterization of a photonic strain sensor in silicon-on-insulator technology

et al. 2012

View full text Add to dashboard Cite

Recently there has been growing interest in sensing by means of optical microring resonators in photonic integrated circuits that are fabricated in silicon-on-insulator (SOI) technology. Taillaert et al. [Proc. SPIE 6619, 661914 (2007)] proposed the use of a silicon-waveguide-based ring resonator as a strain gauge. However, the strong lateral confinement of the light in SOI waveguides and its corresponding modal dispersion where not taken into account. We present a theoretical understanding, as well as experimental results, of strain applied on waveguide-based microresonators, and find that the following effects play important roles: elongation of the racetrack length, modal dispersion of the waveguide, and the strain-induced change in effective refractive index. © 2012 Optical Society of America OCIS codes: 120.4880, 160.1050, 130.7408, 280.4788, 160.6000, 000.2190 Piezoresistive electronic strain gauges are frequently used in micromachined electromechanical systems (MEMS) [1]. Alternatively, all-optical systems can be used, and they have particular benefits, such as being insensitive to electromagnetic interference, not having the danger of initiating gas explosions with electric sparks, and allowing for high speed readout. Guo and co-workers employed an optical polymer microring resonator as an ultrasound sensor, in which the deformation of the resonator was measured by monitoring its shift in resonance frequencies [2,3]. Taillaert et al. [4] proposed the use of a silicon optical microring resonator as a strain gauge. Silicon-on-insulator (SOI) technology has emerged as a focus platform for integrated photonics, with complementary metal-oxide semiconductor (CMOS) production lines, opening the possibility of mass fabrication [5]. Silicon is the commonly used material in MEMS, and we have shown the possibility of micromachining postprocessing of SOI photonic integrated circuits [6]. Strong lateral confinement of the light due to the high refractive index contrast of SOI waveguides (Δn ≈ 2) allows for small device footprint, but also comes with high sensitivity to the exact behavior of the modes in the waveguide, e.g., strong modal dispersion [7,8]. Amemiya et al.[9] reported on the photoelastic effect in strained SOI ring resonators without, however, considering the modal effects, such as dispersion. In this Letter, we first derive a model explaining the effects that play a role when considering the influence of strain on photonic waveguides. Then, we characterize these effects with a novel mechanical setup providing a well-defined strain. We describe the important effects when a strain is applied to a ring resonator that has a racetracklike shape with circumference l, as depicted in Fig. 1. Light is coupled from a connecting waveguide to the racetrack waveguide by means of a multimode interference (MMI) coupler [10,11]. Having such a long racetrack allows us to neglect the effect of the bends and of the coupler. The transmitted spectrum at the output port of the connecting waveguide shows dips at the wavel...

show abstract

“…at. [4] reported on the effect of strain on SOl ring resonators. However, the strong lateral confinement of the light due to the high refractive index contrast in SOl waveguides and its corresponding modal dispersion was not taken into account.…”

mentioning

confidence: 99%

Characterization of the influence of strain on the optical properties of waveguides and microresonators in silicon-on-insulator technology

Westerveld

Harmsma

Schmits

et al. 2011

2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)

View full text Add to dashboard Cite

Silicon-on-insulator (SOl) technology has become one of the focus platforms for photonic integrated circuits (PICs). The CMOS technology opens the possibility for reliable mass fabrication of cost-effective photonic cir cuits. Recently there has been a growing interest in direct optical sensing of, for example, temperature, pressure or strain, using microring resonators [1,2]. Taillaert et. at. [3] proposed the use of a microring resonator as a strain gauge. Amemiya et. at. [4] reported on the effect of strain on SOl ring resonators. However, the strong lateral confinement of the light due to the high refractive index contrast in SOl waveguides and its corresponding modal dispersion was not taken into account. To the best of our knowledge, we are the first to present experimental results and understanding of the effects of an applied strain S in the effective index ne in a SOl-PIC.We fabricated a set of long racetrack-shaped ring resonators (length 1040 f.1m, bend radius 25 f.1m, circum ference I), oriented along the [110] crystalline direction, consisting of a waveguide with dimensions of 1000 x 300 nm. Having a long racetrack enables us to neglect the effects of the bends. We excite the fundamental TM mode using a multimode interference (MMI) coupler ( Fig. 1 b). For the strain measurements we fabricated a novel mechanical set-up ( Fig. la) in which elastic bends are used to provide an uniform strain in the region between the two middle supports, where the microresonator is placed. We apply strain in the longitudinal direction of the racetrack and measure the shift of its resonance wavelengths (Fig 1 c,d), which are fitted to Lorentzian distributions (Fig 1 c). In order to find the wavelength shift, we take the mean shift of 40 resonances and estimate the error as the standard deviation of the random dip-to-dip variation. We find a resonance shift of 0.63 ± 0.08 pm/microstrain.In the analysis of our data, the modal behavior of the light propagating trough the waveguide, including its dispersion, is taken into account. In this description, the resonance wavelength Am of mode m is given by mAm = ne(Ivrn,S)I(S). The first-order influence of strain is then found to be dAm/ dS = Am(ne + dne/ dS) lng, where ng is the (modal) effective group index. Since ne and ng can be accurately found using numerical mode solvers, we are able to calculate the influence of strain on the effective index of the waveguide, resulting in a nel as = -0.69 ± 0.24 index/strain. In addition, we also investigated the influence of the waveguide geometry.

show abstract

Photoelastic Effect in Silicon Ring Resonators

Cited by 15 publications

References 12 publications

Metastable Refractive Index Manipulation in Hydrogenated Amorphous Silicon for Reconfigurable Photonics

Metastable Refractive Index Manipulation in Hydrogenated Amorphous Silicon for Reconfigurable Photonics

Characterization of a photonic strain sensor in silicon-on-insulator technology

Characterization of the influence of strain on the optical properties of waveguides and microresonators in silicon-on-insulator technology

Contact Info

Product

Resources

About