Soliton microcomb based spectral domain optical coherence tomography

Abstract

Spectral domain optical coherence tomography (OCT) is a widely employed, minimally invasive bio-medical imaging technique, which requires a broadband light source, typically implemented by super-luminescent diodes. Recent advances in soliton based photonic integrated frequency combs (soliton microcombs) have enabled the development of low-noise, broadband chipscale frequency comb sources, whose potential for OCT imaging has not yet been unexplored. Here, we explore the use of dissipative Kerr soliton microcombs in spectral domain OCT and show that, by using photonic chipscale Si3N4 resonators in conjunction with 1300 nm pump lasers, spectral bandwidths exceeding those of commercial OCT sources are possible. We characterized the exceptional noise properties of our source (in comparison to conventional OCT sources) and demonstrate that the soliton states in microresonators exhibit a residual intensity noise floor at high offset frequencies that is ca. 3 dB lower than a traditional OCT source at identical power, and can exhibit significantly lower noise performance for powers at the milli-Watt level. Moreover, we demonstrate that classical amplitude noise of all soliton comb teeth are correlated, i.e., common mode, in contrast to superluminescent diodes or incoherent microcomb states, which opens a new avenue to improve imaging speed and performance beyond the thermal noise limit.

Temporal distinguishability in Hong-Ou-Mandel interference for harnessing high-dimensional frequency entanglement

“…Our approach reveals a connection between spectral and temporal degrees of freedom, which may have potential applications in quantum optical coherence tomography and quantum spectral analysis. For example, spectral-domain optical coherence tomography (SD-OCT) is a non-invasive diagnostic technique that can extract the depth information of an optically transparent or translucent sample from spectral analysis [40][41][42] . Since our approach indicates that the two-photon joint spectral intensity is associated to the relative time delay, it can be extended to implement a quantum version of SD-OCT, which is an essential requisite for measuring photon-sensitive biological and chemical samples.…”

Quantum interferometric two-photon excitation spectroscopy

“…The most remarkable outcome of this study is the fact that we provide a connection between sum-frequency intensity and N00N-state interference pattern. In addition to quantum inter-ferometric spectroscopy, which extracts spectral signals from temporal measurements, spectral-domain optical coherence tomography that detects the thickness induced by a transparent material may also be accessible [54,55]. This might motivate the development of novel applications of full-field optical coherence tomography and three-dimensional imaging.…”

Enhanced medical diagnosis for dOCTors: a perspective of optical coherence tomography

“…113 Recently, advancements in soliton-based photonic integrated frequency comb soliton microcombs have accelerated the development of broadband and low-noise chip scale frequency comb sources with the potential for high-resolution OCT deep tissue imaging at 1300 nm. 114 Combining OCT with MPM at these longer wavelengths or even at 1700 nm can enhance tissue penetration. The key enabling elements to improve the imaging penetration depth, depth of focus, and spatial resolution simultaneously are the laser wavelengths and pulse energy, beam shaping concepts, detection schemes, and real-time AI algorithms.…”