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[Crossref]

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[Crossref]

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[Crossref]

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Y. Liu, T. Hao, W. Li, J. Capmany, N. Zhu, and M. Li, “Observation of parity-time symmetry in microwave photonics,” Light Sci. Appl. 7, 38–47 (2018).

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[Crossref]

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[Crossref]

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H. Hodaei, M. A. Miri, A. U. Hassan, W. E. Hayenga, M. Heinrich, D. N. Christodoulides, and M. Khajavikhan, “Single mode lasing in transversely multi‐moded PT‐symmetric microring resonators,” Laser Photon. Rev. 10, 494–499 (2016).

[Crossref]

H. Hodaei, M.-A. Miri, M. Heinrich, D. N. Christodoulides, and M. Khajavikhan, “Parity-time–symmetric microring lasers,” Science 346, 975–978 (2014).

[Crossref]

M.-A. Miri, P. LiKamWa, and D. N. Christodoulides, “Large area single-mode parity-time-symmetric laser amplifiers,” Opt. Lett. 37, 764–766 (2012).

[Crossref]

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[Crossref]

M. Mossammaparast, C. McNeilage, A. Stockwell, J. H. Searls, and M. E. Suddaby, “Low phase noise division from X-band to 640 MHz,” in IEEE Frequency Control Symposium and PDA Exhibition (2002), pp. 685–689.

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[Crossref]

T. M. Fortier, C. W. Nelson, A. Hati, F. Quinlan, J. Taylor, H. Jiang, C. W. Chou, T. Rosenband, N. Lemke, A. Ludlow, D. Howe, C. W. Oates, and S. A. Diddams, “Sub-femtosecond absolute timing jitter with a 10 GHz hybrid photonic-microwave oscillator,” Appl. Phys. Lett. 100, 231111 (2012).

[Crossref]

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[Crossref]

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[Crossref]

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[Crossref]

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[Crossref]

B. Peng, Ş. K. Özdemir, F. Lei, F. Monifi, M. Gianfreda, G. L. Long, S. Fan, F. Nori, C. M. Bender, and L. Yang, “Parity-time-symmetric whispering-gallery microcavities,” Nat. Phys. 10, 394–398 (2014).

[Crossref]

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[Crossref]

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[Crossref]

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[Crossref]

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[Crossref]

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[Crossref]

J. Schindler, A. Li, M. C. Zheng, F. M. Ellis, and T. Kottos, “Experimental study of active LRC circuits with PT symmetries,” Phys. Rev. A 84, 040101 (2011).

[Crossref]

J. Schindler, A. Li, M. C. Zheng, F. M. Ellis, and T. Kottos, “Experimental study of active LRC circuits with PT symmetries,” Phys. Rev. A 84, 040101 (2011).

[Crossref]

M. Mossammaparast, C. McNeilage, A. Stockwell, J. H. Searls, and M. E. Suddaby, “Low phase noise division from X-band to 640 MHz,” in IEEE Frequency Control Symposium and PDA Exhibition (2002), pp. 685–689.

D. Eliyahu, D. Seidel, and L. Maleki, “Phase noise of a high performance OEO and an ultra low noise floor cross-correlation microwave photonic homodyne system,” in IEEE International Frequency Control Symposium (2008), pp. 811–814.

F. Jiang, J. H. Wong, H. Q. Lam, J. Zhou, S. Aditya, P. H. Lim, K. E. K. Lee, P. P. Shum, and X. Zhang, “An optically tunable wideband optoelectronic oscillator based on a bandpass microwave photonic filter,” Opt. Express 21, 16381–16389 (2013).

[Crossref]

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[Crossref]

X. Steve Yao and L. Maleki, “Multiloop optoelectronic oscillator,” IEEE J. Quantum Electron. 36, 79–84 (2000).

[Crossref]

M. Mossammaparast, C. McNeilage, A. Stockwell, J. H. Searls, and M. E. Suddaby, “Low phase noise division from X-band to 640 MHz,” in IEEE Frequency Control Symposium and PDA Exhibition (2002), pp. 685–689.

M. Mossammaparast, C. McNeilage, A. Stockwell, J. H. Searls, and M. E. Suddaby, “Low phase noise division from X-band to 640 MHz,” in IEEE Frequency Control Symposium and PDA Exhibition (2002), pp. 685–689.

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[Crossref]

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[Crossref]

T. M. Fortier, C. W. Nelson, A. Hati, F. Quinlan, J. Taylor, H. Jiang, C. W. Chou, T. Rosenband, N. Lemke, A. Ludlow, D. Howe, C. W. Oates, and S. A. Diddams, “Sub-femtosecond absolute timing jitter with a 10 GHz hybrid photonic-microwave oscillator,” Appl. Phys. Lett. 100, 231111 (2012).

[Crossref]

J. G. Hartnett, C. R. Locke, E. N. Ivanov, M. E. Tobar, and P. L. Stanwix, “Cryogenic sapphire oscillator with exceptionally high long-term frequency stability,” Appl. Phys. Lett. 89, 203513 (2006).

[Crossref]

L. Feng, Z. J. Wong, R.-M. Ma, Y. Wang, and X. Zhang, “Single-mode laser by parity-time symmetry breaking,” Science 346, 972–975 (2014).

[Crossref]

Y. Jiang, J. Yu, Y. Wang, L. Zhang, and E. Yang, “An optical domain combined dual-loop optoelectronic oscillator,” IEEE Photon. Technol. Lett. 19, 807–809 (2007).

[Crossref]

H. Tang, Y. Yu, Z. Wang, and X. Zhang, “Wideband tunable optoelectronic oscillator based on a microwave photonic filter with an ultra-narrow passband,” Opt. Lett. 43, 2328–2331 (2018).

[Crossref]

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[Crossref]

F. Jiang, J. H. Wong, H. Q. Lam, J. Zhou, S. Aditya, P. H. Lim, K. E. K. Lee, P. P. Shum, and X. Zhang, “An optically tunable wideband optoelectronic oscillator based on a bandpass microwave photonic filter,” Opt. Express 21, 16381–16389 (2013).

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[Crossref]

Y. Jiang, J. Yu, Y. Wang, L. Zhang, and E. Yang, “An optical domain combined dual-loop optoelectronic oscillator,” IEEE Photon. Technol. Lett. 19, 807–809 (2007).

[Crossref]

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