Recent advancements in photonic integrated circuits (PICs) have spurred significant interest in embedded ring modulators and switches for their potential applications in telecommunications and computing. These devices offer compact, efficient solutions for signal modulation and routing within integrated photonics platforms. This review explores the latest trends in design, fabrication, and integration techniques for embedded ring modulators and switches. Key topics include novel materials such as silicon photonics, gallium arsenide, and hybrid integration approaches. Additionally, advances in modulation techniques, such as electro-optic and thermo-optic effects, are discussed for their impact on device performance metrics like bandwidth, power efficiency, and scalability. Future prospects focus on overcoming current challenges in fabrication scalability, cost-effectiveness, and compatibility with existing optical networks. By addressing these issues, embedded ring modulators and switches hold promise for enabling next-generation photonic systems with enhanced functionality and performance.

Photonic integrated circuits, Ring modulators, Optical switches

Little BE, Chu ST, Haus HA, Foresi J, Laine JP (1997) Microring Resonator Chnnel Dropping Filters. J Light Technol 15: 998-1005.

Xu Q, Manipatruni S, Schmidt B, Shakya J, Lipson M (2007) 12.5 Gbit/s carrierinjection-based silicon micro-ring silicon modulators. Opt Express 15: 430-436.

Ibrahim TA, Grover R, Kuo LC, Kanakaraju S, Calhoun LC, et al. (2003) Alloptical switching using a critically coupled InP micro-racetrack resonator. Integ Photo Res, Washington DC, USA 91: ITuE4.

Zhang L, Song M, Wu T, Zou L, Beausoleil RG, et al. (2008) Embedded ring resonators for microphotonic applications. Opt Lett 33: 1978-1980.

Nawrocka MS, Liu T, Wang X, Panepucci RR (2006) Tunable silicon microring resonator with wide free spectral range. Appl Phys Lett 89: 071110.

Fetterman M, Chao CP, Forrest SR (1996) Fabrication and Analysis of High-Contrast InGaAsP-InP Mach Zehnder Modulators for Use at 1.55-pm Wavelength. Photo Tech Lett 8: 69-71.

Sadasivan V, Das U (2014) QCSE Tuned Embedded Ring Modulator. Light Tech J 32: 107-114.

Grover R, Ibrahim TA, Kanakaraju S, Lucas L, Calhoun LC, et al. (2004) A tunable GaInAsP-InP optical microring notch filter. Photo Tech Lett IEEE 16:467-469.

Chen H (2007) Development of an 80 Gbit/s InP-based Mach-Zehnder Modulator. Tech Univ Berlin.

Ding XZ, Taijing L, Ong CK, Tan BTG (1994) Effects of impurity concentration on dielectric loss in Zn-doped InP at microwave X-band frequencies. J Appl Phys 75: 7444-7447.

Krupka J, Hartnett JG, Piersa M (2011) Permittivity and microwave absorption of semi-insulating InP at microwave frequencies. Appl Phys Lett 98: 112112.

Agrawal GP (2002) Fiber-Optic Communication Systems (3rdedn) John Wiley and Sons, New York.

Zhang L, Song M, Beausolei RG, Willner AE (2009) A High-Speed Silicon Modulator Based on an Embedded-Ring-Resonator Structure. OSA publish, pp: 22-26.

Seo JK (2006) Study of time-resolved measurement of intensity-dependent refractive index change in GaInAsP waveguides. Tokyo Inst Tech.