title: Breathing laser as an inertia-free swept source for high-quality ultrafast optical bioimaging.
abstract: We demonstrate an all-fiber breathing laser as inertia-free swept source (BLISS), with an ultra-compact design, for the emerging ultrafast bioimaging modalities. The unique feature of BLISS is its broadband wavelength-swept operation (∼60  nm) with superior temporal stability in terms of both long term (0.08 dB over 27 h) and shot-to-shot power variations (2.1%). More importantly, it enables a wavelength sweep rate of >10  MHz (∼7×10⁸  nm/s)—orders-of-magnitude faster than the existing swept sources based on mechanical or electrical tuning techniques. BLISS thus represents a practical and new generation of swept source operating in the unmet megahertz swept-rate regime that aligns with the pressing need for scaling the optical bioimaging speed in ultrafast phenomena study or high-throughput screening applications. To showcase its utility in high-speed optical bioimaging, we here employ BLISS for ultrafast time-stretch microscopy and multi-MHz optical coherence tomography of the biological specimen at a single-shot line-scan rate or A-scan rate of 11.5 MHz.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Wei
authors.forename: Jingjiang
authors.initials: J
authors.lastname: Xu
authors.forename: Yiqing
authors.initials: Y
authors.lastname: Xu
authors.forename: Luoqin
authors.initials: L
authors.lastname: Yu
authors.forename: Jianbing
authors.initials: J
authors.lastname: Xu
authors.forename: Bowen
authors.initials: B
authors.lastname: Li
authors.forename: Andy K S
authors.initials: AK
authors.lastname: Lau
authors.forename: Xie
authors.initials: X
authors.lastname: Wang
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
authors.forename: Kevin K
authors.initials: KK
authors.lastname: Tsia
authors.forename: Kenneth K Y
authors.initials: KK
authors.lastname: Wong
mesh_terms: D005385:Fingers; D006801:Humans; D007834:Lasers; D008168:Lung / Q000166:cytology; D055100:Optical Fibers; D061848:Optical Imaging / Q000295:instrumentation / Q000379:methods*