Programmable True Time Delay Lines Using Integrated Waveguide Meshes

We analyze and explore the potential that waveguide-mesh-based architectures used in programmable photonic integrated circuits can be configured to enable true time optical delay lines, which can find applications in different microwave photonics functionalities, such as beamforming and optical filtering. We also propose and experimentally demonstrate an alternative standalone tunable basic unit (TBU) architecture where its internal coupling device is implemented by means of a dual-drive tunable directional coupler (DD-TDC) that performs independent amplitude beam splitting and phase shifting. Compared to the previous alternatives based on 3-dB balanced Mach–Zehnder interferometers, the DD-TDC reduces by more than two times the insertion losses of TBUs enabling the potential realization of larger meshes with a three-fold enhanced step-time resolution. Bandwidth and robustness analysis are also considered.

[1]  Jacob B Khurgin,et al.  Tunable wideband optical delay line based on balanced coupled resonator structures. , 2009, Optics letters.

[2]  Richard Soref,et al.  Electro-optical switching using coupled photonic crystal waveguides. , 2002, Optics express.

[3]  Z. Sheng,et al.  A Compact and Low-Loss MMI Coupler Fabricated With CMOS Technology , 2012, IEEE Photonics Journal.

[4]  José Capmany,et al.  Reconfigurable lattice mesh designs for programmable photonic processors and universal couplers , 2016, ICTON.

[5]  Daniel Pérez,et al.  Silicon Photonics Rectangular Universal Interferometer , 2017 .

[6]  Herwig Kogelnik,et al.  Electro‐optically switched coupler with stepped Δβ reversal using Ti‐diffused LiNbO3 waveguides , 1976 .

[7]  Marc Sorel,et al.  Compact tunable directional couplers in SOI , 2013, CLEO: 2013.

[8]  Chris G. H. Roeloffzen,et al.  Programmable photonic signal processor chip for radiofrequency applications , 2015, 1505.00094.

[9]  D. Blumenthal,et al.  Programmable eye-opener lattice filter for multi-channel dispersion compensation using an integrated compact low-loss silicon nitride platform. , 2016, Optics express.

[10]  G. Cong,et al.  Demonstration of a 3-dB directional coupler with enhanced robustness to gap variations for silicon wire waveguides. , 2014, Optics express.

[11]  Ivana Gasulla,et al.  Towards programmable microwave photonics processors , 2017, 2017 Optical Fiber Communications Conference and Exhibition (OFC).

[12]  Reck,et al.  Experimental realization of any discrete unitary operator. , 1994, Physical review letters.

[13]  Ana Sánchez,et al.  Silicon nitride photonics: from visible to mid-infrared wavelengths , 2018, OPTO.

[14]  Abu Sahmah Mohd Supa'at.  Implementation of thermo-optic waveguide photonics switch using polymer material , 2013, 2013 IEEE 4th International Conference on Photonics (ICP).

[15]  J. J. Veselka,et al.  Simultaneous modulation and wavelength multiplexing with a tunable Ti:LiNbO3 directional coupler filter , 1985 .

[16]  Ivana Gasulla,et al.  Microwave photonics: The programmable processor , 2016 .

[17]  C. Roeloffzen,et al.  Silicon nitride microwave photonic circuits. , 2013, Optics express.

[18]  David A. B. Miller,et al.  Perfect optics with imperfect components , 2015 .

[19]  Leimeng Zhuang,et al.  On-chip, CMOS-compatible, hardware-compressive integrated photonic beamformer based on WDM , 2013, 2013 IEEE International Topical Meeting on Microwave Photonics (MWP).

[20]  Keigo Iizuka,et al.  Engineering Optics , 1985 .

[21]  Chris G. H. Roeloffzen,et al.  Separate carrier tuning scheme for integrated optical delay lines in photonic beamformers , 2011, 2011 International Topical Meeting on Microwave Photonics jointly held with the 2011 Asia-Pacific Microwave Photonics Conference.

[22]  K. Jinguji,et al.  Synthesis of coherent two-port lattice-form optical delay-line circuit , 1995 .

[23]  Fan Zhang,et al.  Broadband silicon photonic directional coupler using asymmetric-waveguide based phase control. , 2015, Optics express.

[24]  Steven G. Johnson,et al.  Strain-tunable silicon photonic band gap microcavities in optical waveguides , 2004 .

[25]  Ivana Gasulla,et al.  Toward Programmable Microwave Photonics Processors , 2018, Journal of Lightwave Technology.

[26]  Daniel Pérez López,et al.  Integrated Microwave Photonic Processors using Waveguide Mesh Cores , 2017 .

[27]  Hong Cai,et al.  Ultralow Power Silicon Photonics Thermo-Optic Switch With Suspended Phase Arms , 2011, IEEE Photonics Technology Letters.

[28]  Linjie Zhou,et al.  Continuously tunable ultra-thin silicon waveguide optical delay line , 2017 .

[29]  J. Bowers,et al.  Low-Loss Continuously Tunable Optical True Time Delay Based on Si3N4 Ring Resonators , 2018, IEEE Journal of Selected Topics in Quantum Electronics.

[30]  N. Harris,et al.  Efficient, compact and low loss thermo-optic phase shifter in silicon. , 2014, Optics express.

[31]  William S. Rabinovich,et al.  Effective index tuning in micro-opto-mechanical structures using gradient electric forces , 2016, 2016 IEEE Photonics Society Summer Topical Meeting Series (SUM).

[32]  Thomas R. Clark,et al.  Tuning Optimization of Ring Resonator Delays for Integrated Optical Beam Forming Networks , 2017, Journal of Lightwave Technology.

[33]  José Capmany,et al.  Software-defined reconfigurable microwave photonics processor. , 2015, Optics express.

[34]  Humphreys,et al.  An Optimal Design for Universal Multiport Interferometers , 2016, 1603.08788.

[35]  Tao Chu,et al.  Optical directional coupler based on Si-wire waveguides , 2005, First IEEE International Conference on Group IV Photonics, 2004..

[36]  Tohru Mogami,et al.  Low-loss silicon wire waveguides for optical integrated circuits , 2016 .

[37]  R. Schmidt,et al.  Switched directional couplers with alternating Δ Β , 1976 .

[38]  Ke Li,et al.  Multipurpose silicon photonics signal processor core , 2017, Nature Communications.

[39]  J. O'Brien,et al.  Universal linear optics , 2015, Science.