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Schonenberger, S. et al. “Silicon photonic microcavities for optical switching.” Lasers and Electro-Optics 2009 and the
European Quantum Electronics Conference. CLEO Europe -
EQEC 2009. European Conference on. 2009. 1. ©2009 IEEE.
http://dx.doi.org/10.1109/CLEOE-EQEC.2009.5192041
Institute of Electrical and Electronics Engineers
Final published version
Thu May 26 09:53:42 EDT 2016 http://hdl.handle.net/1721.1/60307
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Bert J.
Sophie Schonenberger', Marcus S. Dahlem,,2, Thilo Stoferle', Nikolaj Moll', Rainer F. Mahrt',
Offrein', Erich P. Ippen", Thorsten Wahlbrink
3
,
Jens Bolten
Michael Forst4, Heinrich Kurz", Stephan Gotzinger
3
,
5
,
Tobias Plotzing", Michael Waldow4,
Vahid Sandoghdar"
1. IBM Research GmbH, Zurich Research Laboratory, Saumerstrasse 4, 8803 Ruschlikon, Switzerland
2. Research Laboratory ofElectronics, Massachus etts Institute ofTechnol ogy, Cambridge , MA 02139, USA
3. Advan ced Microelectronic Center, Aach en (AMICA), AMO GmbH, Otto-Blumenthal-Strasse 25,52074 Aachen , Germany
4. Institut fur Halbleitertechnik, RWTH Aachen University, Sommerfeldstrasse 24,52074 Aachen, Germany
5. Nano-Photonics Group, Laboratory of Physical Chemistry, ETH Zurich, 8093 Zurich, Switzerland
The prospect of silicon photonics is particularly promising: the fabrication is mostly compatible with standard CMOS technology and it will offer tremendous advantages over traditional optical communication solutions with respect to size, cost and power . There has been a significant activity in the development of photonic circuits having a density approaching that of modem electronic circuits for future chip-to-chip or onchip optical interconnects. Therefore, an ultrasmall footprint of integrated optical components is of pivotal importance.
Here, we report on two specific types of integrated microcavities, namely circular grating resonators [I]
(CGRs) , see Fig. 1 (a), and 10 photonic crystal cavities [2-5], see Fig. 1 (b). These device structures open up the feasibility of highly integrated ultrafast electro-optical modulators due to their small active optical volume ofless than 1 um'. Furthermore, they have a very small device area of 15 x 15 Jlm
2 for the CGRs and 10 x 1 Jlm
2 for the
10 photonic crystal cavities . The structures are designed by optimizing the quality factor Q of the isolated cavities using 3D fmite-difference time-domain (FDTD) methods. For the isolated cavities theoretical Q-values up to 10
6 are reached for both types of devices. By adding in- and out-coupling waveguides the Q-factor will reduce to a few thousands , corresponding to photon lifetimes and therefore optical switching times in the range of a few picoseconds [6]. The linear optical properties of such cavities are investigated by transmission spectroscopy. By means of scanning near-field optical microscopy (SNOM) we are able to probe the spatial distribution of resonant optical modes and parasitic losses. High speed all-optical switching is demonstrated by optical excitation of charge carriers within the cavity . Recent work towards electrically active device structures achieved through a carrier-injection-based p-i-n junction is presented .
(a) (b)
Fig. 1 Scanning electron microscopy image (a) of a circular grating resonator with in-and out-coupling waveguides and (b) of a ID photoni c crystal micro cavity device with electrical contact s.
References
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2746 (2003) .
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