Optical coherence of Er3+^{3+}:Y2_2O3_3 ceramics for telecommunication quantum technologies

We report an optical homogeneous linewidth of 580 $\pm$ 20 Hz of Er$^{3+}$:Y$_2$O$_3$ ceramics at millikelvin temperatures, narrowest so far in rare-earth doped ceramics. We show slow spectral diffusion of $\sim$2 kHz over a millisecond time scale. Temperature, field dependence of optical coherence and spectral diffusions reveal the remaining dephasing mechanism as elastic two-level systems in polycrystalline grain boundaries and superhyperfine interactions of Er$^{3+}$ with nuclear spins. In addition, we perform spectral holeburning and measure up to 5 s hole lifetimes. These spectroscopic results put Er$^{3+}$:Y$_2$O$_3$ ceramics as a promising candidate for telecommunication quantum memories and light-matter interfaces

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 7

Antibiotic circles of samples loading GEN and control samples. GEN group: (a) CCS46-pH1, (b) CCS46-pH5, (c) CCS46-pH9; Control group: (d) CCS46-pH1, (e) CCS46-pH5, (f) CCS46-pH9.</p

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 1

Photographs of CMC/chitosan blend solutions (gel) under different pH conditions and the Schematic diagrams of the interaction between CMC and chitosan molecules: photographs of ratio group. (a) chitosan, (b) CS28, (c) CS46, (d) CS64, (e) CS82, (f) CMC; photographs of pH group (g) CCS46-pH1, (h) CCS46-pH5, (i) CCS46-pH9, (j) CCS46-pH13; Schematic diagrams: (k) CCS46-pH1, (l) CCS46-pH5 and CCS46-pH9, (m) CCS46-pH13.</p

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 5

Swelling degree (SD) and weight loss (WL) of the samples. (a) SD of ratio group, (b) SD of pH group, (c): WL of ratio group, (d): WL of pH group.</p

The parameters (ratios and pH values) and viscosities of CMC/chitosan blend solutions.

The parameters (ratios and pH values) and viscosities of CMC/chitosan blend solutions.</p

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 3

SEM photographs of the composite sponges. Surface: (a) CCS46-pH1, (b) CCS46-pH5, (c) CCS46-pH13; cross-section: (d) CCS46-pH1, (e) CCS46-pH5, (f) CCS46-pH13.</p

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 4

FT-IR spectra (a) and TGA spectra (b) of the pH group samples.</p

Raw data of FT-IR spectra, TGA spectra, swelling degree, weight loss and drug cumulative release of sponges.

(XLSX)</p

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 6

Drug cumulative release of sponges. (a) GEN of ratio group, (b) GEN of pH group (c) IBU of ratio group, (d) IBU of pH group, (e) ROX of ratio group, (f) ROX of pH group.</p

Preparation, characterization and <i>in vitro</i> release study of drug-loaded sodium carboxy-methylcellulose/chitosan composite sponge - Fig 2

Morphology of the composite sponge. (a) flattened sponge, (b) folded sponge, (c) recovered sponge.</p