Distributed Feedback Lasers Based on Thiophene/Phenylene Co‐Oligomer Single Crystals

Abstract

Organic crystals have great potential for the applications in laser devices. This article presents an effective approach for fabrication of distributed feedback single crystal lasers. With the laser interference ablation method, high quality grating structures have been fabricated on the organic single‐crystalline thin film materials. The relationship between the depth, periodicity, and laser fluence is discussed. The optical properties, such as photoluminescence, and diffractive properties are studied in detail. With the appropriate period, strong laser emission has been observed from these devices. Distributed feedback lasing is demonstrated from the laser interference ablated organic single crystals for the first time.

Functional organic single crystals for solid-state laser applications

“…When the thickness is less than 1 µm, ASE occurs mainly at S 0 ‐S 1 transitions; when the thickness is larger than 2 µm, S 0 ‐S 2 transitions dominate ASE spectrum. We have also observed similar results in BP2T crystal . ASE firstly occurs at S 0 ‐S 2 transitions for thick crystals.…”

Superkinetic Growth of Oval Organic Semiconductor Microcrystals for Chaotic Lasing

“…The lasing is highly reproducible for the stadium‐shaped BP2T microcrystals with an average threshold of 5.0 ± 0.1 µJ cm −2 , which is sixfold lower than those of the hexagonal BP2T microcrystals (29.8 ± 0.9 µJ cm −2 ) as shown in Figure S10a–d (Supporting Information). Note that the lasing threshold of ≈5.0 µJ cm −2 is lower than most BP2T crystal lasers reported previously, [ 27,40,41 ] which can be ascribed to the high Q ‐factor and small mode volume of the stadium‐shaped microcavity. Above the lasing threshold, the mode linewidth jumps down to ≈0.078 nm (Figure 3c), revealing a significant increase of temporal coherence.…”

“…The stadium‐shaped BP2T microcrystals can function as both optical cavities and gain media, [ 40,41 ] and therefore support laser oscillation. We measured the optically pumped lasing behaviors of the BP2T microcrystals on a micro‐photoluminescence system (Figure S9, Supporting Information).…”

Processing condition dependence of time-resolved photoluminescence in thiophene/phenylene co-oligomer microcavities

“…Recently, distributed feedback laser cavities and microdisk cavities with areas of over 1 mm 2 have been demonstrated on TPCO crystals. 18,19) However, we found that the fluorescence lifetime of the microcavity was much shorter than that of the nonprocessed part. One possible reason for the lifetime shortening is the Purcell effect, which has been observed in inorganic microcavities and also in organic microcavities.…”