[1] A. Politi, M. J. Cryan, J. G. Rarity, S. Y. Yu, J. L. O’Brien. Silica-on-silicon waveguide quantum circuits. Science, 320, 646-649(2008).

[2] I. A. Walmsley. Quantum optics: science and technology in a new light. Science, 348, 525-530(2015).

[3] C. L. Xiong, B. Bell, B. J. Eggleton. CMOS-compatible photonic devices for single-photon generation. Nanophotonics, 5, 427-439(2016).

[4] A. S. Solntsev, A. A. Sukhorukov. Path-entangled photon sources on nonlinear chips. Rev. Phys., 2, 19-31(2017).

[5] A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, D. N. Christodoulides. Observation of PT-symmetry breaking in complex optical potentials. Phys. Rev. Lett., 103, 093902(2009).

[6] C. E. Ruter, K. G. Makris, R. El Ganainy, D. N. Christodoulides, M. Segev, D. Kip. Observation of parity-time symmetry in optics. Nat. Phys., 6, 192-195(2010).

[7] V. V. Konotop, J. K. Yang, D. A. Zezyulin. Nonlinear waves in PT-symmetric systems. Rev. Mod. Phys., 88, 035002(2016).

[8] S. V. Suchkov, A. A. Sukhorukov, J. H. Huang, S. V. Dmitriev, C. Lee, Y. S. Kivshar. Nonlinear switching and solitons in PT-symmetric photonic systems. Laser Photon. Rev., 10, 177-213(2016).

[9] B. Vest, M. C. Dheur, E. Devaux, A. Baron, E. Rousseau, J. P. Hugonin, J. J. Greffet, G. Messin, F. Marquier. Anti-coalescence of bosons on a lossy beam splitter. Science, 356, 1373-1376(2017).

[10] G. S. Agarwal, K. N. Qu. Spontaneous generation of photons in transmission of quantum fields in PT-symmetric optical systems. Phys. Rev. A, 85, 031802(2012).

[11] B. He, S. B. Yan, J. Wang, M. Xiao. Quantum noise effects with Kerr-nonlinearity enhancement in coupled gain-loss waveguides. Phys. Rev. A, 91, 053832(2015).

[12] B. He, L. Yang, M. Xiao. Dynamical phonon laser in coupled active-passive microresonators. Phys. Rev. A, 94, 031802(2016).

[13] S. Vashahri-Ghamsari, B. He, M. Xiao. Continuous-variable entanglement generation using a hybrid PT-symmetric system. Phys. Rev. A, 96, 033806(2017).

[14] F. Setzpfandt, A. S. Solntsev, J. Titchener, C. W. Wu, C. L. Xiong, R. Schiek, T. Pertsch, D. N. Neshev, A. A. Sukhorukov. Tunable generation of entangled photons in a nonlinear directional coupler. Laser Photon. Rev., 10, 131-136(2016).

[15] M. Ornigotti, A. Szameit. Quasi PT-symmetry in passive photonic lattices. J. Opt., 16, 065501(2014).

[16] C. M. Caves, D. D. Crouch. Quantum wide-band traveling-wave analysis of a degenerate parametric-amplifier. J. Opt. Soc. Am. B, 4, 1535-1545(1987).

[17] D. Klyshko. Photons and Nonlinear Optics(1988).

[18] A. N. Poddubny, I. V. Iorsh, A. A. Sukhorukov. Generation of photon-plasmon quantum states in nonlinear hyperbolic metamaterials. Phys. Rev. Lett., 117, 123901(2016).

[19] D. A. Antonosyan, A. S. Solntsev, A. A. Sukhorukov. Effect of loss on photon-pair generation in nonlinear waveguide arrays. Phys. Rev. A, 90, 043845(2014).

[20] W. Vogel, D.-G. Welsch. Quantum Optics(2006).

[21] M. Liscidini, J. E. Sipe. Stimulated emission tomography. Phys. Rev. Lett., 111, 193602(2013).

[22] L. G. Helt, M. J. Steel. Effect of scattering loss on connections between classical and quantum processes in second-order nonlinear waveguides. Opt. Lett., 40, 1460-1463(2015).

[23] F. Lenzini, A. N. Poddubny, J. Titchener, P. Fisher, A. Boes, S. Kasture, B. Haylock, M. Villa, A. Mitchell, A. S. Solntsev, A. A. Sukhorukov, M. Lobino. Direct characterization of a nonlinear photonic circuit’s wave function with laser light(2017).