Optical gain of the1.54 μmemission in MBE-grown Si:Er nanolayers

Abstract

We present investigations of the optical gain cross section of 1.54 m Er-related emission at 4.2 K in Si/Si:Er molecular-beam-epitaxy-grown multinanolayers. This ultranarrow ͑full width at half maximum below 8 eV͒ emission originating from the unique Er-related optical complex, Er-1 center, ensures the best condition to achieve stimulated emission. The experiments were carried out using a combination of the variable stripe length and shifting excitation spot techniques under pulsed and continuous-wave excitations. The comparison of results for both excitation regimes enables to estimate an optical gain within the strong optical losses due to the free carrier absorption. Based on these measurements, the upper limit of the optical gain cross section of 10 −17 cm 2 and the gain coefficient of 8.8 cm −1 are deduced.

Photonic Properties of Er-Doped Crystalline Silicon

“…These losses are most probably due to absorption of the Er-1 emission induced by free carriers in the excited part of the multinanolayer structure. This issue is currently under investigation [84].…”

“…For that purpose, Si/Si:Er multinanolayer structures have been grown by the similar procedure of SMBE on a semi-insulating (SOI) substrate. In this specific case, the investigated sample consisted of 20 periods of 3-6 nm Si:Er layers separated by 90 nm spacers of undoped Si [83], [84]. After an appropriate annealing process, five intense sharp PL lines typical of the Er-1 center have been observed (inset of Fig.…”

“…In order to investigate that possibility, variable stripe length (VSL) and shifted excitation spot (SES) [86], [87] measurements have been conducted in an SMBE-grown sample [84]. In Fig.…”

Photoluminescence responses of Si nanocrystal to differing pumping conditions

“…[20][21][22] For the PL efficiency measurement, we used an S80-type integrated sphere to collect the PL emissions (Labsphere) with a He-Cd laser as an excitation source, a HP8453-type UV-Vis photospectrometer (Agilent) for absorbance measurement, and a Fluorolog-3 type photospectrometer (Jobin-Yvon) to collect PL signals. Electronic mail: minglu@fudan.ac.cn.…”

Single-crystal erbium chloride silicate nanowires as a Si-compatible light emission material in communication wavelength

“…Such a narrow linewidth indicates high crystal quality of the material and large absorption and large emission cross sections, although within a narrower wavelength window. This is especially critical for getting a high optical gain [32]. Well separated sharp emission lines have been observed in erbium doped materials with very low erbium concentration [33].…”