Reversible multiplexing for optical information recording, erasing, and reading-out in photochromic BaMgSiO4:Bi3+ luminescence ceramics

Abstract

Optical data storage technology has many advantages over the traditional solid-state and magnetic storage technology, such as low cost, multi-dimensional storage, and rewritable capability. Therefore, the optical data storage technology has been in increasing demand for optical storage media. Herein, the photochromic and photoluminescence properties of BaMgSiO 4 :Bi 3+ ceramics were investigated. The BaMgSiO4:Bi3+ ceramics showed reversible photochromism from gray to pink upon alternating the 254 nm ultraviolet light and 532 nm laser irradiation. This is caused by the electron trapping and de-trapping in the oxygen vacancies of the BaMgSiO 4 :Bi 3+ host. This reversible behavior of photochromism was applied to fabricate different patterns on the surface of the BaMgSiO 4 :Bi 3+ ceramics, which exhibited the reversible dual-mode optical information recording and erasing abilities. The photoluminescence reversible modulation of the BaMgSiO 4 :Bi 3+ ceramics was obtained through the photochromic phenomenon. This modification behavior of luminescence could be applied to read-out the recording information in the BaMgSiO 4 :Bi 3+ ceramics. The coloration and bleaching of BaMgSiO 4 :Bi 3+ ceramics were dependent on the time of light stimulation, which facilitated multiplexing encoding. This photoluminescence and photochromism multiplexing of the BaMgSiO 4 :Bi 3+ ceramics enhanced the optical data storage capability.

Highly Responsive Photochromic Ceramics for High‐Contrast Rewritable Information Displays

“…[15,26,33,48] Upon 420 nm illumination, the electrons located at the valence band or intermediate defects are excited to higher energy and some of them are captured by intrinsic defects such as oxygen vacancies, forming F-centers. [14,26,43] Subsequently, part of the incident light can be absorbed by the ceramic to release the electrons trapped by defects, changing the reflectivity and color of the ceramics. The electrons captured by the shallow traps are unstable and most of them are released at room temperature.…”

“…Compared to organic photochromic materials, the merits of excellent thermal stability, long cycling life, and stable chemical resistance make inorganic photochromic materials preferable for optical devices. [7] Currently, the extensively studied inorganic photochromic materials can be divided into three categories: transition metal oxides (TiO 2 , WO 3 , MoO 3 , and Nb 2 O 5 ), [8][9][10][11][12][13] robust oxides (BaMgSiO 4 , Sr 3 YNa(PO 4 ) 3 F, and Sr 2 SnO 4 ), [14][15][16][17][18][19][20][21][22] and ferroelectrics ((K 0.5 Nb 0.5 )NbO 3 (KNN), Na 0.5 Bi 4.5 Ti 4 O 15 , and Na 0.5 Bi 2.5 Nb 2 O 9 ). [6,[23][24][25][26][27][28] On the one hand, transition metal oxides usually possess a large coloration contrast but suffer from a slow response, poor reversibility, and weak chemical resistance.…”

“…[15,32] However, directly recording information with a portable laser is still difficult for these inorganic photochromic materials due to their slow photoresponse or weak coloration contrast. [12,14,25] Thus, it is challenging to combine both fast response time and strong coloration contrast in inorganic materials to enable hand-writable information display.…”

Designing Photochromic Materials with Large Luminescence Modulation and Strong Photochromic Efficiency for Dual‐Mode Rewritable Optical Storage

“…For BaMgSiO 4 : M (M = Ce 3+ , Mn 2+ , or Nd 3+ ) ceramics, the defects of V ′′ Ba , V ′′ Mg , and are generated during the high‐temperature sintering and ion incorporation. [ 37–39 ] These defects are located between the conduction band (CB) and the valence band (VB). Upon 310 nm illumination, the electrons located at the VB or intermediate defects are excited to higher energy, and some of them are trapped by the defects, such as oxygen vacancies, forming F‐centers.…”

“…[ 11–15 ] In contrast, inorganic materials exhibit superior thermal stability, excellent fatigue resistance, and facile preparation, showing great potential in optical memory applications. Different inorganic materials, such as transition metal oxides (WO 3 and TiO 2 ), [ 16–23 ] ferroelectric ceramics ((K 0.5 Na 0.5 )NbO 3 , Na 0.5 Bi 2.5 Nb 2 O 9 ) [ 23–31 ] and robust oxides (BaMgSiO 4 , Sr 2 SnO 4 ) [ 32–44 ] have been developed for photochromic applications together with the investigation of their luminescence modulation behavior. Despite the achievement of reversible luminescence modulation based on photochromic behavior, simultaneously achieving a large luminescence modulation and a strong photochromic efficiency in inorganic materials is still challenging.…”