Abstract

Many applications, including laser (LIDAR) mapping, free-space optical communications, and spatially resolved optical sensors, demand compact, robust solutions to steering an optical beam. Fine target addressability (high steering resolution) in these systems requires simultaneously achieving a wide steering angle and a small beam divergence, but this is difficult due to the fundamental trade-offs between resolution and steering range. So far, to our knowledge, chip-based two-axis optical phased arrays have achieved a resolution of no more than 23 resolvable spots in the phased-array axis. Here we report, using non-uniform emitter spacing on a large-scale emitter array, a dramatically higher-performance two-axis steerable optical phased array fabricated in a 300 mm CMOS facility with over 500 resolvable spots and 80° steering in the phased-array axis (measurement limited) and a record small divergence in both axes (0.14°). Including the demonstrated steering range in the other (wavelength-controlled) axis, this amounts to two-dimensional beam steering to more than 60,000 resolvable points.

© 2016 Optical Society of America

Full Article  |  PDF Article
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References

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J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

A. Yaacobi, J. Sun, M. Moresco, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 4575 (2014).
[Crossref]

2013 (3)

W. Guo, P. Binetti, and C. Althouse, IEEE J. Sel. Top. Quantum Electron. 19, 8500508 (2013).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

J. C. Hulme, J. K. Doylend, and J. E. Bowers, Opt. Express 21, 19718 (2013).
[Crossref]

2012 (3)

2011 (3)

2010 (1)

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P. F. Van Kessel, L. J. Hornbeck, R. E. Meier, and M. R. Douglass, Proc. IEEE 86, 1687 (1998).
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H. Unz, IRE Trans. Antennas Propag. 8, 222 (1960).
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Abediasl, H.

Abiri, B.

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W. Guo, P. Binetti, and C. Althouse, IEEE J. Sel. Top. Quantum Electron. 19, 8500508 (2013).
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Antona, J.-C.

Baets, R.

Bigo, S.

Binetti, P.

W. Guo, P. Binetti, and C. Althouse, IEEE J. Sel. Top. Quantum Electron. 19, 8500508 (2013).
[Crossref]

Binetti, P. R. A.

W. Guo, P. R. A. Binetti, M. L. Masanovic, L. A. Johansson, and L. A. Coldren, “Large-scale InP photonic integrated circuit packaged with ball grid array for 2D optical beam steering,” in IEEE Photonics Conference, Bellevue, WA, 2013, Vol. 2, pp. 651–652.

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Bordel, D.

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K. F. Braun, Elektrotech. Polytech. Rundsch., 1, Nov. 1905.

Chakravarty, S.

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

Chen, R. T.

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

D. Kwong, A. Hosseini, Y. Zhang, and R. T. Chen, Appl. Phys. Lett. 99, 3 (2011).
[Crossref]

Coldren, L. A.

Cole, D. B.

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

J. Sun, E. S. Hosseini, A. Yaacobi, D. B. Cole, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 367 (2014).
[Crossref]

Coolbaugh, D.

Covey, J.

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

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[Crossref]

Doylend, J. K.

Duan, G. H.

Efimov, O.

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W. Guo, P. Binetti, and C. Althouse, IEEE J. Sel. Top. Quantum Electron. 19, 8500508 (2013).
[Crossref]

W. Guo, P. R. A. Binetti, M. L. Masanovic, L. A. Johansson, and L. A. Coldren, “Large-scale InP photonic integrated circuit packaged with ball grid array for 2D optical beam steering,” in IEEE Photonics Conference, Bellevue, WA, 2013, Vol. 2, pp. 651–652.

Hajimiri, A.

Hashemi, H.

Heck, M. J. R.

Hornbeck, L. J.

P. F. Van Kessel, L. J. Hornbeck, R. E. Meier, and M. R. Douglass, Proc. IEEE 86, 1687 (1998).
[Crossref]

Hosseini, A.

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

D. Kwong, A. Hosseini, Y. Zhang, and R. T. Chen, Appl. Phys. Lett. 99, 3 (2011).
[Crossref]

Hosseini, E. S.

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

J. Sun, E. S. Hosseini, A. Yaacobi, D. B. Cole, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 367 (2014).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

Houdré, R.

Hulme, J. C.

Jágerská, J.

Jany, C.

Johansson, L. A.

W. Guo, P. R. A. Binetti, M. L. Masanovic, L. A. Johansson, and L. A. Coldren, “Large-scale InP photonic integrated circuit packaged with ball grid array for 2D optical beam steering,” in IEEE Photonics Conference, Bellevue, WA, 2013, Vol. 2, pp. 651–652.

Komorowska, K.

Kwong, D.

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

D. Kwong, A. Hosseini, Y. Zhang, and R. T. Chen, Appl. Phys. Lett. 99, 3 (2011).
[Crossref]

Lamponi, M.

Le Liepvre, A.

Le Thomas, N.

Leake, G.

Lelarge, F.

Lorcy, L.

Make, D.

Masanovic, M. L.

W. Guo, P. R. A. Binetti, M. L. Masanovic, L. A. Johansson, and L. A. Coldren, “Large-scale InP photonic integrated circuit packaged with ball grid array for 2D optical beam steering,” in IEEE Photonics Conference, Bellevue, WA, 2013, Vol. 2, pp. 651–652.

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[Crossref]

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Miglo, A.

Moresco, M.

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H. Nikkhah, K. Van Acoleyen, and R. Baets, Ann. Telecommun. 68, 57 (2012).
[Crossref]

Patterson, P.

Peters, J. D.

Poingt, F.

Rekhi, A.

Rogier, H.

Sayyah, K.

Schaffner, J.

Seurin, J.-F.

Simonneau, C.

Su, Z.

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

Subbaraman, H.

Sun, J.

A. Yaacobi, J. Sun, M. Moresco, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 4575 (2014).
[Crossref]

J. Sun, E. S. Hosseini, A. Yaacobi, D. B. Cole, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 367 (2014).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

Timurdogan, E.

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

Unz, H.

H. Unz, IRE Trans. Antennas Propag. 8, 222 (1960).
[Crossref]

Vacondio, F.

Van Acoleyen, K.

Van Kessel, P. F.

P. F. Van Kessel, L. J. Hornbeck, R. E. Meier, and M. R. Douglass, Proc. IEEE 86, 1687 (1998).
[Crossref]

Watts, M. R.

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

J. Sun, E. S. Hosseini, A. Yaacobi, D. B. Cole, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 367 (2014).
[Crossref]

A. Yaacobi, J. Sun, M. Moresco, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 4575 (2014).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

White, C.

Xu, G.

Xu, X.

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

Yaacobi, A.

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

A. Yaacobi, J. Sun, M. Moresco, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 4575 (2014).
[Crossref]

J. Sun, E. S. Hosseini, A. Yaacobi, D. B. Cole, G. Leake, D. Coolbaugh, and M. R. Watts, Opt. Lett. 39, 367 (2014).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

Zhang, Y.

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen, Opt. Lett. 39, 941 (2014).
[Crossref]

D. Kwong, A. Hosseini, Y. Zhang, and R. T. Chen, Appl. Phys. Lett. 99, 3 (2011).
[Crossref]

Ann. Telecommun. (1)

H. Nikkhah, K. Van Acoleyen, and R. Baets, Ann. Telecommun. 68, 57 (2012).
[Crossref]

Appl. Phys. Lett. (1)

D. Kwong, A. Hosseini, Y. Zhang, and R. T. Chen, Appl. Phys. Lett. 99, 3 (2011).
[Crossref]

IEEE J. Sel. Top. Quantum Electron. (2)

W. Guo, P. Binetti, and C. Althouse, IEEE J. Sel. Top. Quantum Electron. 19, 8500508 (2013).
[Crossref]

J. Sun, E. Timurdogan, A. Yaacobi, Z. Su, E. S. Hosseini, D. B. Cole, and M. R. Watts, IEEE J. Sel. Top. Quantum Electron. 20, 8201115 (2014).
[Crossref]

IEEE Photon. Technol. Lett. (1)

D. Kwong, A. Hosseini, J. Covey, X. Xu, Y. Zhang, S. Chakravarty, and R. T. Chen, IEEE Photon. Technol. Lett. 26, 991 (2014).
[Crossref]

IRE Trans. Antennas Propag. (1)

H. Unz, IRE Trans. Antennas Propag. 8, 222 (1960).
[Crossref]

J. Lightwave Technol. (1)

Nature (1)

J. Sun, E. Timurdogan, A. Yaacobi, E. S. Hosseini, and M. R. Watts, Nature 493, 195 (2013).
[Crossref]

Opt. Express (8)

Opt. Lett. (5)

Proc. IEEE (1)

P. F. Van Kessel, L. J. Hornbeck, R. E. Meier, and M. R. Douglass, Proc. IEEE 86, 1687 (1998).
[Crossref]

Other (3)

K. F. Braun, Elektrotech. Polytech. Rundsch., 1, Nov. 1905.

J. K. Doylend, M. J. R. Heck, J. T. Bovington, J. D. Peters, and J. E. Bowers, “Free-space beam steering using silicon waveguide surface gratings,” in IEEE Photonic Society 24th Annual Meeting, Arlington, VA (2011), pp. 547–548.

W. Guo, P. R. A. Binetti, M. L. Masanovic, L. A. Johansson, and L. A. Coldren, “Large-scale InP photonic integrated circuit packaged with ball grid array for 2D optical beam steering,” in IEEE Photonics Conference, Bellevue, WA, 2013, Vol. 2, pp. 651–652.

Supplementary Material (1)

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Figures (5)

Fig. 1.
Fig. 1. Device concept. (a) A simplified drawing of the device, showing only five channels for clarity (our device has 128); (i)–(iv) are described in the text. The dashed line indicates where the chip may be diced in order to edge-couple light. After passing through the star coupler and phase tuners, the emitted light traces out the green cone and is steerable using the wavelength (θ axis) and by tuning the phase of each channel (ψ axis). (b) An optical microscope image of the star coupler. The input waveguide is at center left; the 128 output waveguides begin near the center and fan out toward the right of the image. The scale bar is 500 μm. (c) A tilted scanning electron microscope image of the emitter with the cladding removed. The waveguide with grating notches is in the center, and the dark lines above and below show an isolation trench between emitters. The scale bar is 2 μm. The inset is a simplified drawing of the emitter at a slightly different angle so the scanning electron microscope image can be understood. The grating etch is indicated in blue.
Fig. 2.
Fig. 2. (a) and (b) Far-field simulation along ψ for uniform and non-uniform emitter pitches, respectively. The beam is shown steered to different angles in 5° increments [two angles in (a) and ten angles in (b)]. We avoid aliasing and therefore achieve a much larger steering range using the non-uniformly spaced emitters. (c) A zoom-in of the main lobe from (a) and (b), showing it is the same in both cases.
Fig. 3.
Fig. 3. Condensing and steering the beam. (a) The test setup, indicating the light rays used to align the imaging system to the emitters (blue rays, lens 1 only), and the rays used to characterize the far-field beam (red, lenses 1 and 2). (b) Without phase control, the phase at each emitter is initially arbitrary; thus we observe a smeared-out elliptical line in the far field. It is an ellipse because we are imaging the edge of the cone shown in Fig. 1(a). (c) and (d) The far field after aligning the phase at each emitter, for the OPA with non-uniform and uniform pitches, respectively. (e) The condensed beam for the uniformly spaced OPA, showing 75 separate measurements of the beam steered to different angles across about 10°; each measurement is a different color.
Fig. 4.
Fig. 4. (a) The uniformly spaced emitter showing aliased lobes at ±5°. (b) The cross section of (a) in the OPA-steered direction (along the dashed blue line) compared to the simulation. The non-uniformly spaced OPA has the same typical beam width. (c) The cross section of (a) in the wavelength-steered direction (green). The cross section in the other direction is overlaid for comparison (blue dotted). (d) Images at three wavelengths stitched together; the image boundary is indicated by a dashed gray line. For these measurements, we used the uniformly spaced OPA so the direction of wavelength tuning is clear, but the non-uniform OPA behaves in the same manner.
Fig. 5.
Fig. 5. (a) The beam from the non-uniformly spaced OPA, steered to five angles across 80°. (b) Elliptical cross sections of Fig. 3(e) with the simulated result overlaid. The gray area is the viewable range of our imaging setup. The worst side lobe level in these five measurements is noted on the graph.

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