The rapid development of global telecommunication, cloud computing, big data, consumer electronics create increasing demands to expand the capacity and rate of data transmission for next generation broadband optical communication. It raises a great challenge for current rare‐earth ions doped fiber amplifiers due to the narrow emission bandwidth of rare‐earth ions. In this context, broadband near‐infrared (NIR) emitter based optical amplifiers are in urgent demand. Here, broadband optical amplification in S + C + L bands is achieved for the first time in PbS quantum dot (QD)‐doped low‐melting‐point glass fiber. With the pump of a 976 nm laser, the on‐off gain of PbS QD‐doped fiber (PQDF) ranges from 1.4 to 8.7 dB in 1500–1630 nm, while that of PbS QD‐doped glass ranges from 6.9 to 8.4 dB in 1530–1630 nm. Both QD‐doped glass and optical fiber show tunable luminescence covering the entire optical communication windows (O + E + S + C + L + U). The much higher quantum yield of PbS QDs in glass than that of colloidal QDs, the ultra‐broad and controllable emission bands and bandwidth make PbS QDs doped glass and fiber promising for applications in next generation broadband optical fiber amplifiers and tunable fiber lasers.

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Nowadays, the world is on the threshold of Industries 4.0 era featuring high automation, high informatization, and high networking. To deal with the massive data encountered in the Industrial 4.0 era, novel data storage mediums with high switching speed, large storage capacity, low power consumption, and long service lifetime are urgently required. Traditionally, information can be written and read in the forms of magnetism, [1] electric signal, [2] and optical signal. [3][4][5] Magnetic storage technologies have been widely applied in tapes, floppy disks, to hard disks for decades. Although magnetic storage capacity was refreshed repeatedly and even reached the storage limit in the latest single-atom magnets data storage technique, [6,7] the magnetic response of materials on the microsecond timescale and high power consumption are still needed to be improved. Data storage technologies based on electrical signals are mainly resistive random-access memory (RRAM) and phase-change random-access memory (PRAM). [8,9] Since RRAM and PRAM are both implement data storage by electric-field-driven resistive switching, so they unavoidably involve the layer-by-layer structures, which increases the sophistication of device fabrication and limits the bit size. Moreover, the switching rate from high resistance to low resistance of RRAM and PRAM depends heavily on the ion migration rate, which limits the data writing/reading speed.Compared to magnetic storage and electric storage, optical storage has the merits of fast writing/reading speed, huge storage capacity, long-endurance, easy fabrication, and low maintenance cost. Besides commercially available optical storage mediums such as compact disc (CD), digital video disc digital (DVD), and blue-ray disc (BD), huge-storage-capacity 3D optical storage techniques were successively developed based on laser-induced refractive index variation, [10] color center/defect formation, ionic valence state variation, [11][12][13] phase change, [14,15] nanograting formation, [16,17] nanocrystal precipitation, [18] and so on. Among them, luminescent nanocrystals were believed to be good candidates for data bits due to their potential multi-dimensional storage capabilities (based on decay time, wavelength, intensity, or polarization).In recent years, inorganic lead halide perovskite quantum dots have been used in various optoelectronic fields for their excellent luminescence properties, such as narrow emission bands, ultra-wide tunable emission wavelength, and high quantum efficiency. In this paper, different from luminescence optimization in most research, luminescence degradation of perovskite quantum dots is addressed by femtosecond laser irradiation and successfully used for three-dimensional data storage in CsPbBr 3 quantum dots doped glass. Photoluminescence (PL) degradation can be finely modulated by adjusting the laser parameters. PL degradation mechanism, investigated by optical spectroscopy and morphology characterization, is attributed to laser-induced decomposition, recrystallizatio...

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CsPbI 3 perovskite quantum dots (QDs) doped borosilicate glass was prepared by the process of melt-quenching and subsequent annealing. With the introduction of ZnO to the parent glass as the glass network intermediate, the optical properties of the resultant samples are dramatically enhanced. Both the photoluminescence (PL) intensity and photoluminescence quantum yield (PLQY) shows a strong dependence on ZnO concentration as ZnO is found to facilitate the precipitated of the QDs by reducing the connectivity of three-dimensional glass network built from SiO 4 tetrahedrons. The tunable visible-band PL emission of the CsPbI 3 QD-doped glass could find potential applications in white LEDs and lasers.

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