Tunable megahertz bandwidth microwave photonic notch filter based on a silica microsphere cavity.

We propose and experimentally demonstrate a tunable microwave photonic notch filter with a megahertz order bandwidth based on a silica microsphere cavity coupled by an optical microfiber. The silica microsphere with a quality factor of hundreds of millions offers a full width at half-maximum bandwidth down to the order of megahertz in the transmission spectrum. Due to the coupling flexibility between the microcavity and the optical microfiber, the bandwidth and suppression ratio can be tuned and optimized to get a rejection ratio beyond 30 dB. The tunability of over 15 GHz is also achieved. To the best of our knowledge, this single-stopband microwave photonic filter has the narrowest bandwidth filter that has ever been experimentally demonstrated. This microwave photonic notch filter shows distinct advantages of high selectivity, compactness, flexibility, and low insertion loss.

[1]  David Marpaung,et al.  Frequency agile microwave photonic notch filter with anomalously high stopband rejection. , 2013, Optics letters.

[2]  David Marpaung,et al.  Tunable narrowband microwave photonic filter created by stimulated Brillouin scattering from a silicon nanowire. , 2015, Optics letters.

[3]  Guang-Can Guo,et al.  Brillouin-scattering-induced transparency and non-reciprocal light storage , 2014, Nature Communications.

[4]  Dingshan Gao,et al.  Photonic measurement of microwave frequency using a silicon microdisk resonator , 2015 .

[5]  David Marpaung,et al.  Si₃N₄ ring resonator-based microwave photonic notch filter with an ultrahigh peak rejection. , 2013, Optics express.

[6]  D. Marpaung,et al.  Low-power, chip-based stimulated Brillouin scattering microwave photonic filter with ultrahigh selectivity , 2014, 1412.4236.

[7]  K. Song,et al.  Compact Ultra-Wideband (UWB) Bandpass Filters With Multiple Notched Bands , 2010, IEEE Microwave and Wireless Components Letters.

[8]  H. Haus,et al.  Microring resonator channel dropping filters , 1997 .

[9]  G. R. Aiello,et al.  Ultra-wideband wireless systems , 2003 .

[10]  Dingshan Gao,et al.  Compact Notch Microwave Photonic Filters Using On-Chip Integrated Microring Resonators , 2013, IEEE Photonics Journal.

[11]  José Capmany,et al.  Microwave photonics combines two worlds , 2007 .

[12]  Jian Wang,et al.  Ultra-high peak rejection notch microwave photonic filter using a single silicon microring resonator , 2015, 2015 Optical Fiber Communications Conference and Exhibition (OFC).

[13]  Sisi Tan,et al.  Photonic Hilbert Transformer Employing On-Chip Photonic Crystal Nanocavity , 2014, Journal of Lightwave Technology.

[14]  Hailin Wang,et al.  Optomechanical Dark Mode , 2012, Science.

[15]  A. Tünnermann,et al.  Nonlinear thermal effects in optical microspheres at different wavelength sweeping speeds. , 2008, Optics express.

[16]  A. Matsko,et al.  Narrowband tunable photonic notch filter. , 2009, Optics letters.

[17]  José Capmany,et al.  Integrated microwave photonics , 2013 .

[18]  Zach DeVito,et al.  Opt , 2017 .