Source: http://aoot.osa.org/oe/abstract.cfm?uri=oe-18-25-26613
Timestamp: 2019-04-25 09:48:00+00:00

Document:
We present the first demonstration of frequency conversion by simultaneous second- and third-harmonic generation in a silicon photonic crystal nanocavity using continuous-wave optical excitation. We observe a bright dual wavelength emission in the blue/green (450–525 nm) and red (675–790 nm) visible windows with pump powers as low as few microwatts in the telecom bands, with conversion efficiencies of ∼ 10−5/W and ∼ 10/W2 for the second- and third-harmonic, respectively. Scaling behaviors as a function of pump power and cavity quality-factor are demonstrated for both second- and third order processes. Successful comparison of measured and calculated emission patterns indicates that third-harmonic is a bulk effect while second-harmonic is a surface-related effect at the sidewall holes boundaries. Our results are promising for obtaining practical low-power, continuous-wave and widely tunable multiple harmonic generation on a silicon chip.
K. J. Vahala, “Optical microcavities,” Nature 424, 839–846 (2003).
R. Salem, M. A. Foster, A. C. Turner, D. F. Geraghty, M. Lipson, and A. L. Gaeta, “Signal regeneration using low-power four-wave mixing on a silicon chip,” Nat. Photonics 2, 35–38 (2007).
A. C. Turner, M. A. Foster, A. L. Gaeta, and M. Lipson, “Ultra-low power parametric frequency conversion in a silicon microring resonator,” Opt. Express 16, 4881–4887 (2008).
H. Rong, S. Xu, Y.-H. Kuo, V. Sih, O. Cohen, O. Raday, and M. Paniccia, “Low-threshold continuous-wave Raman silicon laser,” Nat. Photonics 1, 232–237 (2007).
Y. R Shen, The Principles of Nonlinear Optics (Wiley, New York, 1984).
R. Boyd, Nonlinear Optics (Academic Press, California, 1992).
M. A. Foster, A. C. Turner, J. E. Sharping, B. S. Schmidt, M. Lipson, and A. L. Gaeta, “Broad-band optical parametric gain on a silicon photonic chip,” Nature 441, 960–963 (2006).
T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Kerr-nonlinearity optical parametric oscillation in an ultrahigh-Q toroid microcavity,” Phys. Rev. Lett. 93, 083904 (2004).
O. Boyraz, T. Indukuri, and B. Jalali, “Self-phase-modulation induced spectral broadening in silicon waveguides,” Opt. Express 12, 829–834 (2004).
A. R. Cowan, G. W. Rieger, and J. F. Young, “Nonlinear transmission of 1.5 μm pulses through single-mode silicon-on-insulator waveguide structures,” Opt. Express 12, 1611–1621 (2004).
E. Dulkeith, Y. A. Vlasov, X. Chen, N. C. Panoiu, and R. M. Osgood. “Self-phase-modulation in submicron silicon-on-insulator photonic wires,” Opt. Express 14, 5524–5534 (2006).
S. M. Spillane, T. J. Kippenberg, and K. J. Vahala, “Ultra-low threshold Raman laser using a spherical dielectric microcavity,” Nature 415, 621–623 (2002).
A. Liu, H. Rong, O. Cohen, M. Paniccia, and D. Hak, “Net optical gain in low-loss silicon-on-insulator waveguide by stimulated Raman scattering,” Opt. Express 112, 4261–4267 (2004).
H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, “A continuous-wave Raman silicon laser,” Nature 433, 725–728 (2005).
B. Corcoran, C. Monat, C. Grillet, D. J. Moss, B. J. Eggleton, T. P. White, L. O’Faolain, and T. F. Krauss, “Green light emission in silicon through slow-light enhanced third-harmonic generation in photonic-crystal waveguides,” Nat. Photonics 3, 206–209 (2009).
M. Notomi, K. Yamada, A. Shinya, J. Takahashi, C. Takahashi, and I. Yokohama, “Extremely large group-velocity dispersion of line-defect waveguides in silicon photonic crystal slabs,” Phys. Rev. Lett. 87, 253902 (2001).
W. Bogaerts, R. Baets, P. Dumon, V. Wiaux, S. Beckx, D. Taillaert, B. Luyssaert, J. Van Campenhout, P. Bienstman, and D. Van Thourhout, “Nanophotonic waveguides in silicon-on-insulator fabricated with CMOS technology,” J. Lightwave Technol. 23, 401–412 (2006).
L. O’Faolain, X. Yuan, D. McIntyre, S. Thoms, H. Chong, R. M. De La Rue, and T. F. Krauss, “Low-loss propagation in photonic crystal waveguides,” Electron. Lett. 42, 1454–1455 (2006).
Y. Akahane, T. Asano, B. S. Song, and S. Noda, “High-Q photonic nanocavity in a two-dimensional photonic crystal,” Nature 425, 944–947 (2003).
B. S. Song, S. Noda, T. Asano, and Y. Akahane, “Ultra-high-Q photonic doubleheterostructure nanocavity,” Nat. Mater. 4, 207–210 (2005).
T. F. Krauss, “Slow light in photonic crystal waveguides,” J. Phys. D 40, 2666–2670 (2007).
T. Baba, “Slow light in photonic crystals,” Nat. Photonics 2, 465–473 (2008).
J. Bravo-Abad, A. Rodriguez, P. Bermel, S. G. Johnson, J. D. Joannopoulos, and M. Soljacic, “Enhanced nonlinear optics in photonic-crystal microcavities,” Opt. Express 15, 16161–16176 (2007).
M. W. McCutcheon, J. F. Young, G. W. Rieger, D. Dalacu, S. Frédérick, P. J. Poole, and R. L. Williams, “Experimental demonstration of second-order processes in photonic crystal microcavities at submilliwatt excitation powers,” Phys. Rev. B 76, 245104 (2007).
D. Coquillat, G. Vecchi, C. Comaschi, A. M. Malvezzi, J. Torres, and M. Le Vassor d’Yerville, “Enhanced second- and third-harmonic generation and induced photoluminescence in a two-dimensional GaN photonic crystal,” Appl. Phys. Lett. 87, 101106 (2005).
S. Combrié, A. De Rossi, Q. V. Tran, and H. Benisty, “GaAs photonic crystal cavity with ultra-high Q: microwatt nonlinearity at 1.55 μm,” Opt. Lett. 33, 1908–1910 (2008).
K. Rivoire, Z. Lin, F. Hatami, W. T. Masselink, and J. Vučković, “Second-harmonic generation in gallium phosphide photonic crystal nanocavities with ultralow continuous wave pump power,” Opt. Express 17, 22609–22615 (2009).
M. Falasconi, L. C. Andreani, A. M. Malvezzi, M. Patrini, V. Mulloni, and L. Pavesi, “Bulk and surface contributions to second-order susceptibility in crystalline and porous silicon by second-harmonic generation,” Surf. Science 481, 105–112 (2001).
T. V. Dolgova, A. I. Maidykovski, M. G. Martemyanov, A. A. Fedyanin, O. A. Aktsipetrov, G. Marowsky, V. A. Yakovlev, and G. Mattei, “Giant microcavity enhancement of second-harmonic generation in all-silicon photonic crystals,” Appl. Phys. Lett. 81, 2725 (2002).
P. P. Markowicz, H. Tiryaki, H. Pudavar, P. N. Prasad, N. N. Lepeshkin, and R. W. Boyd, “Dramatic enhancement of third-harmonic generation in three dimensional photonic crystals,” Phys. Rev. Lett. 92, 083903 (2004).
M. G. Martemyanov, E. M. Kim, T. V. Dolgova, A. A. Fedyanin, and O. A. Aktsipetrov, “Third-harmonic generation in silicon photonic crystals and microcavities,” Phys. Rev. B 70, 073311 (2004).
C. Comaschi, G. Vecchi, A. M. Malvezzi, M. Patrini, G. Guizzetti, M. Liscidini, L. C. Andreani, D. Peyrade, and Y. Chen, “Enhanced third-harmonic reflection and diffraction in silicon-on-insulator photonic waveguides,” Appl. Phys. B 81, 305–311 (2005).
N. Bloembergen, R. K. Chang, S. S. Jha, and C. H. Lee, “Optical second-harmonic generation in reflection from media with inversion symmetry,” Phys. Rev. 174, 813 (1968).
J. A. Litwin, J. E. Sipe, and H. M. van Driel, “Picosecond and nanosecond second-harmonic generation from centrosymmetric semiconductors,” Phys. Rev. B 31, 5543 (1985).
P. Guyot-Sionnest, W. Chen, and Y. R. Shen, “General considerations on optical second-harmonic generation from surfaces and interfaces,” Phys. Rev. B 33, 8254 (1986).
J. E. Sipe, D. J. Moss, and H. M. van Driel, “Phenomenological theory of optical second- and third-harmonic generation from cubic centrosymmetric crystals,” Phys. Rev. B 35, 1129 (1987).
R. Jones, H. Rong, A. Liu, A. W. Fang, and M. J. Paniccia, “Net continuous wave optical gain in a low loss silicon-on-insulator waveguide by stimulated Raman scattering,” Opt. Express 13, 519–525 (2005).
T. Tanabe, M. Notomi, S. Mitsugi, A. Shinya, and E. Kuramochi, “All-optical switches on a silicon chip realized using photonic crystal nanocavities,” Appl. Phys. Lett. 87, 151112 (2005).
A. Witvrouwa, B. Du Bois, P. De Moor, A. Verbist, C. Van Hoof, H. Bender, and K. Baert, “A comparison between wet HF etching and vapor HF etching for sacrificial oxide removal,” Proc. SPIE 4174130–141 (2000).
N.-V.-Q. Tran, S. Combrié, and A. De Rossi, “Directive emission from high-Q photonic crystal cavities through band folding,” Phys. Rev. B 79, 041101 (2009).
M. Toishi, D. Englund, A. Faraon, and J. Vučković, “High-brightness single photon source from a quantum dot in a directional emission nanocavity,” Opt. Express 17, 14618–14626 (2009).
S. L. Portalupi, M. Galli, C. Reardon, T. F. Krauss, L. O’Faolain, L. C. Andreani, and D. Gerace, “Planar photonic crystal cavities with far-field optimization for high coupling efficiency and quality factor,” Opt. Express 18, 16064–16073 (2010).
The 3D FDTD simulations shown in this work have been performed with commercial software from Lumerical Solutions Inc.
L. C. Andreani, D. Gerace, and M. Agio, “Gap maps, diffraction losses, and exciton-polaritons in photonic crystal slabs,” Photon. Nanostruct. Fundam. Appl. 2, 103–110 (2004).
D. Gerace and L. C. Andreani, “Effects of disorder on propagation losses and cavity Q-factors in photonic crystal slabs,” Photon. Nanostruct. Fundam. Appl. 3, 120–128 (2005).
M. McCutcheon, G. W. Rieger, I. W. Cheung, J. F. Young, D. Dalacu, S. Frédéric, P. J. Poole, G. C. Aers, and R. Williams, “Resonant scattering and second-harmonic spectroscopy of planar photonic crystal microcavities,” Appl. Phys. Lett. 87, 221110 (2009).
M. Galli, S. L. Portalupi, M. Belotti, L. C. Andreani, L. O’Faolain, and T. F. Krauss, “Light scattering and Fano resonances in high-Q photonic crystal nanocavities,” Appl. Phys. Lett. 94, 071101 (2009).
M. Notomi, A. Shinya, S. Mitsugi, G. Kira, E. Kuramochi, and T. Tanabe, “Optical bistable switching action of Si high-Q photonic-crystal nanocavities,” Opt. Express 13, 2678–2687 (2005).
T. Uesugi, B. S. Song, T. Asano, and S. Noda, “Investigation of optical nonlinearities in an ultra-high-Q Si nanocavity in a two-dimensional photonic crystal slab,” Opt. Express 14, 377–386 (2006).
M. P. Nezhad, A. Simic, O. Bondarenko, B. Slutsky, A. Mizrahi, L. Feng, V. Lomakin, and Y. Fainman, “Room-temperature subwavelength metallo-dielectric lasers,” Nat. Photonics 4, 395–399 (2010).
T. Tanabe, K. Nishiguchi, A. Shinya, E. Kuramochi, H. Inokawa, M. Notomi, K. Yamada, T. Tsuchizawa, T. Watanabe, H. Fukuda, H. Shinojima, and S. Itabashi, “Fast all-optical switching using ion-implanted silicon photonic crystal nanocavities,” Appl. Phys. Lett. 90, 031115 (2007).
Fig. 1 The system under consideration. (a) SEM image of the fabricated device; the enlarged holes around the cavity are marked in yellow. (b) Far-field intensity profile calculated for the cavity shown in (a) by 3D FDTD simulation. (c) Sketch of the SHG and THG emission from our PhC cavity.
Fig. 2 Experimental demonstration of simultaneous SHG and THG. (a) Resonant scattering spectrum (left) of a PhC nanocavity with fundamental mode at λc = 1353.6 nm (pump wavelength). SHG and THG emission spectra (right) at red and blue wavelengths λSH = 676.8 nm and λTH = 451.2 nm, respectively. (b) Resonant scattering spectrum (left) of a PhC nanocavity with fundamental mode at λc = 1575.1 nm (pump wavelength). SHG and THG emission spectra (right) at deep-red and green wavelengths λSH = 787.5 nm and λTH = 525 nm, respectively.
Fig. 5 Q-factor and lineshape scalings. (a) Upper panel, Q-factor (right axis) and corresponding coupling efficiency ηcav (left axis) of the far-field modified PhC nanocavities as a function of the holes enlargement Δr. Lower panel, the product Qηcav. (b) SHG and THG emission intensity vs. Q-factor for the same series of PhC cavities. The HG signals peak around Q ∼ 3 × 104, which corresponds to the cavity with Δr = 6 nm in (a) that has the highest Qηcav product. (c) Normalized SHG and THG emission intensity (see text) as a function of the cavity Q factor showing clear Q2 and Q3 scaling, respectively. (d) Resonant scattering spectrum of a PhC nanocavity with Q = 5.2 × 103 (black dots), and best-fit to a Lorentzian lineshape (black line, L). SHG and THG spectra recorded while scanning the pump laser across the cavity resonance (red and green dots, respectively). Red and green lines interpolating the SHG and THG data are the squared (L2) and cubed (L3) Lorentzians, respectively.
Fig. 3 SH and TH near- and far-field emission. (a),(b) Ex and Ey components of the calculated electric field inside the PhC cavity at the resonance frequency. (c),(d) Spectrally filtered optical image of the SHG and THG emission taken with a high sensitivity Si CCD, respectively. (e),(f) Corresponding experimental Fourier images (see methods) showing the polar far-field emission profile of the SHG and THG light. (g),(h) Calculated far-field patterns (see methods).
Fig. 4 Power scaling and conversion efficiency. (a) SHG and THG emission intensity versus coupled pump power for a PhC nanocavity with coupling efficiency 0.2 and quality factor Q = 5.2 × 103, at fixed pump wavelength. (b) SHG and THG emission intensity versus coupled pump power for a PhC nanocavity with coupling efficiency 0.12 and quality factor Q = 3.2 × 104. Pump wavelength has been varied for increasing pump power to account for thermo-optical induced red-shift of the cavity mode.
(2) P y ( 2 ω c ) = χ 311 ( 2 ) E x 2 ( ω c ) .

References: V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V.