Cavity-enhanced eigenmode and angular hybrid multiplexing in holographic data storage systems

Abstract

Abstract:Resonant optical cavities have been demonstrated to improve energy efficiencies in Holographic Data Storage Systems (HDSS). The orthogonal reference beams supported as cavity eigenmodes can provide another multiplexing degree of freedom to push storage densities toward the limit of 3D optical data storage. While keeping the increased energy efficiency of a cavity enhanced reference arm, image bearing holograms are multiplexed by orthogonal phase code multiplexing via Hermite-Gaussian eigenmodes in a Fe:LiNbO 3 medium with a 532 nm laser at two Bragg angles. We experimentally confirmed write rates are enhanced by an average factor of 1.1, and page crosstalk is about 2.5%. This hybrid multiplexing opens up a pathway to increase storage density while minimizing modification of current angular multiplexing HDSS.

Eigenmode multiplexing with SLM for volume holographic data storage

“…In experiments, a 0.6° angle increment is used [6]. The images in the dotted lines are the objects, indicating the locations.…”

“…The cross-correlation of the arbitrary complex field h and g in grating space can be expressed as follows [6].…”

“…We experimentally demonstrated that orthogonal phase code multiplexing by using eigenmode of cavity combined with angular multiplexing has affinity to existing angular multiplexing while optically enhancing dynamic range and/or sensitivity of material [6].…”

“…Conventionally, phase plates are adopted to generate orthogonal modes [6]. Eigenmode multiplexing with static phase plates is reported to yield a crosstalk as low as 2.5%.…”

Advanced multimodal laser imaging tool for urothelial carcinoma diagnosis (AMPLITUDE)

“…Other possible approaches to design fiber pulsed sources operating in the spectral region around 1.7 µm include Raman shifting the pulsed radiation emitted by an Er-fiber laser [17,23] and special Tm-doped active fibers in combination with optical elements suppressing amplification at 1.85 µm [24,25]. The all-fiber femtosecond Raman-based laser approach was notable for the shortest pulses (65 fs [17]) in this wavelength region so far.…”