Organic doped crystal laser capable of realizing three-band tunable emission

Abstract

The invention discloses a three-band tunable organic doped crystal laser, which is characterized in that B3BtS is used as a subject, BP3T is used as an object (the doping ratio is 0.1-2.0%), and a two-dimensional single crystal is prepared through a physical vapor transport method. Under 400nm femtosecond laser pumping, low pumping energy (3.7 [mu] J / cm < 2 >) triggers 555nm lasing of an object; medium pumping energy (15.0 [mu] J / cm < 2 >) competes with stimulated radiation due to FRET (Fluorescence Resonance Energy Transfer), so that double-peak coexistence of 463nm / 555nm is realized; fRET is suppressed by high pumping energy (30.07 mu J / cm < 2 >), and 490nm lasing of a main body is triggered. The laser is low in threshold value (the lowest value is 3.70 mu J / cm < 2 >), the wave band is dynamically adjustable, and the laser is suitable for a miniaturized multicolor laser light source.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic lasers, and particularly provides an organic doped crystal laser capable of realizing three-band tunable emission. BACKGROUND

[0002] Controllable multi-color laser sources are the core demand of modern photonics technology, and are the core technology of the next generation of optical communication, high-definition display and sensing systems. Multi-wavelength lasing needs to balance the exciton population of different light-emitting centers, and traditional methods are easily restricted by uneven energy transfer efficiency. Host-guest doping systems exhibit the potential of multi-color light emission through intermolecular energy transfer (such as resonance energy transfer, FRET), but how to precisely control the energy distribution to realize the synchronous output of multi-wavelength laser is still a challenge. The present application proposes an organic crystal doping method by precisely designing the size matching and energy transfer path of host-guest molecules, which realizes the dynamic switching of three-color laser emission. Traditional multi-color lasers need to independently control multiple light-emitting centers, resulting in complex device structure. The present application realizes the dynamic switching of three bands by a single doped crystal, simplifying the system architecture. SUMMARY

[0003] The purpose of the present application is to provide an organic doped crystal laser capable of realizing three-band tunable emission. Compared with inorganic lasers, organic solid-state lasers are easy to prepare, low in cost, and suitable for a wider range of applications.

[0004] To achieve the above purpose, the present application discloses an organic doped crystal laser capable of realizing three-band tunable emission, comprising: a two-dimensional single crystal composed of a host material B3BtS, and a guest material BP3T doped in the host material.

[0005] The doping mass percentage of the guest material BP3T is 0.1%-2.0%;

[0006] The laser realizes dynamic switching of three-band laser under 400nm femtosecond laser pumping by adjusting the pumping energy:

[0007] The low pumping region (3.7-15.0μJ / cm 2 ) preferentially emits 555nm laser;

[0008] The medium pumping region (15.0-30.0μJ / cm 2 ) simultaneously emits 463nm and 555nm dual-band laser;

[0009] The high pumping region (>30.0μJ / cm 2 ) triggers 490nm laser, forming three-band tunable emission.

[0010] The two-dimensional single crystal is prepared by a physical vapor phase transmission method, and the specific steps include the following:

[0011] (1) grinding B3BtS and BP3T powders together in a mass ratio of 0.1%-2.0%;

[0012] (2) growing the crystal in a double-temperature zone tube furnace under the conditions of a first temperature zone of 420 DEG C, a second temperature zone of 220 DEG C, a carrier gas flow of 100 mL / min, and a pressure of 0.1 Pa.

[0013] The three-waveband lasers correspond to 463 nm (0-1 transition of the host), 490 nm (0-2 transition of the host), and 555 nm (guest lasing), respectively.

[0014] The emission intensity is adjusted by the doping concentration; when the doping concentration increases from 0.1% to 2.0%, the intensity of the host emission peak gradually decreases, and the intensity of the guest emission peak increases.

[0015] The laser is used for optical communication or a multi-color display system.

[0016] The application designs and synthesizes a two-dimensional organic single crystal of B3BtS doped with BP3T, and the crystal has a three-waveband tunable light-induced laser emission property. The application prepares a multi-color organic light-induced laser through doping, and the laser threshold values of a 2% doped crystal at 555 nm, 463 nm and 490 nm are 3.70 μJ / cm 2 , 15.18 μJ / cm 2 and 30.07 μJ / cm 2 , which is reduced by more than 40% compared with the threshold value of a traditional organic laser. The application first discovers a pump energy threshold window (15.0-30.0 μJ / cm 2 ) of a stimulated radiation rate and FRET competition, which is a key to realize double-peak coexistence. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced as follows:

[0018] Figure 1 It is the host and guest molecular structure of the doped crystal designed and synthesized in the embodiment one of the application.

[0019] Figure 2 It is the condition and method of growing the doped single crystal by the physical vapor phase transmission method in the embodiment two of the application.

[0020] Figure 3 It is the morphology and luminescence photo of the host-guest crystal and the doped single crystal under the fluorescence microscope, the absorption and emission spectrum of the host-guest crystal and the doped crystal, and the emission spectrum of the crystal with different doping concentrations.

[0021] Figure 4 Figure 4 is a laser behavior of a 2% doped single crystal at 400 nm femtosecond light according to an embodiment of the present application. DETAILED DESCRIPTION

[0022] The embodiments of the present application will be described in detail with reference to the drawings and examples, so that the application can be understood as how to apply technical means to solve technical problems and achieve technical effects. It should be noted that, as long as there is no conflict, each feature in each embodiment of the present application can be combined with each other to form a technical solution within the protection scope of the present application.

[0023] Embodiment 1

[0024] A method for synthesizing a doped organic two-dimensional single crystal, the specific steps comprising: grinding guest material BP3T powder and host material B3BtS powder in a mortar according to a mass ratio of 0.1%, 0.5%, 1.0%, and 2.0% to form a mixed powder. Grinding for 30 minutes under inert gas protection to avoid material oxidation.

[0025] For example, the mass of the host and guest powders for preparing a 2% doped crystal in the above steps is 1 g and 20 mg, respectively.

[0026] Embodiment 2

[0027] As shown in Figure 1 , Figure 2 , 3 mg of the mixed powder was uniformly dispersed in a pre-cleaned quartz boat and placed in the first temperature zone of a double-temperature zone tube furnace, the temperature was set to 420°C for 5 hours, a clean glass sheet was placed in the second temperature zone of the double-temperature zone tube furnace, the temperature was set to 220°C for 5 hours. Under a pressure of 0.1 Pa, argon was used as the carrier gas at a flow rate of 100 ml / min, and after 5 hours of treatment, a two-dimensional doped crystal was obtained. The obtained single crystal has a thickness of 1-5 μm and a lateral size of ≥100 μm.

[0028] Embodiment 3

[0029] As shown in Figure 3As shown, the transferred host-guest crystals and crystals with different doping concentrations were placed under a fluorescence microscope for observation. The fluorescence micrographs showed that the crystals had good light waveguide and optical confinement effects, and the edges had strong luminescence. The crystal transmission absorption spectrum showed that the host crystal absorption peak wavelength was at 350 nm and 420 nm, and the luminescence peak wavelength was at 435 nm, 463 nm, 490 nm and 525 nm; the guest crystal absorption peak wavelength was at 422 nm and 466 nm, and the luminescence peak wavelength was at 572 nm, 618 nm and 670 nm; the 2% doped crystal absorption peak wavelength was at 356 nm and 420 nm, and the luminescence peak wavelength was at 555 nm and 605 nm. As the doping concentration gradually increased from 0.1% to 2%, the intensity at the emission peak position of the host crystal gradually decreased. As shown in Figure 3 , the fluorescence micrograph of the 2% doped crystal showed strong edge luminescence, confirming the light waveguide effect; the absorption peaks 356 / 420 nm and the emission peaks 555 / 605 nm had a Stokes shift.

[0030] Example 4

[0031] As shown in Figure 4 , the laser behavior spectrum and intensity change curve, the laser behavior characterization of the crystal: the transferred 2% doped crystal was placed under a 400 nm femtosecond laser, and its laser behavior was observed and collected. The left graph shows the change in the luminescence spectrum of the crystal as the pump energy increases. In the low pump region (3.7-15.0 μJ / cm 2 ), the guest molecule 555 nm lasing is preferentially produced; in the middle pump region (15.0-30.0 μJ / cm 2 ): the host stimulated radiation rate competes with FRET, resulting in the coexistence of 463 nm (host 0-1 transition) and 555 nm double peaks; in the high pump region: the stimulated radiation rate suppresses FRET, triggering 490 nm (0-2 transition) laser, and the inset is a photo of the three-color laser emission of the crystal above the threshold. The right graph shows the change in the luminescence intensity as the pump energy increases, showing a clear S-shaped nonlinear relationship. The threshold of the 555 nm laser is 3.70 μJ / cm 2 , the threshold of the 463 nm laser is 15.18 μJ / cm 2 , and the threshold of the 490 nm laser is 30.07 μJ / cm 2 . The test was carried out in a nitrogen atmosphere to avoid air quenching.

Claims

1. An organic-doped crystal laser capable of achieving three-band tunable emission, characterized in that: include: A two-dimensional single crystal composed of a host material B3BtS and a guest material BP3T doped in the host material; The doping mass percentage of the guest material BP3T is 0.1%-2.0%; The laser is pumped by a 400nm femtosecond laser and achieves dynamic switching of three-band lasers by adjusting the pump energy: Low pump region (3.7–15.0 μJ / cm 2 ) preferentially emits 555nm laser; Mid-pump region (15.0–30.0 μJ / cm 2 ) Simultaneously emits 463nm and 555nm dual-band lasers; High pump region (>30.0μJ / cm 2 ) triggers the 490nm laser to form a three-band tunable emission.

2. The laser according to claim 1, wherein The two-dimensional single crystal is prepared by physical vapor transport method, and the specific steps include: (1) Grinding B3BtS and BP3T powders at a mass ratio of 0.1% to 2.0%; (2) In a dual-temperature zone tubular furnace, crystals were grown at 420°C in the first zone, 220°C in the second zone, a carrier gas flow rate of 100 mL / min, and a pressure of 0.1 Pa.

3. The laser according to claim 1, wherein The three-band lasers correspond to: 463 nm (host 0-1 transition), 490 nm (host 0-2 transition), and 555 nm (guest lasing).

4. The laser according to claim 1, wherein The doping concentration adjusts the emission intensity: when the doping concentration increases from 0.1% to 2.0%, the host emission peak intensity gradually decreases, and the guest emission peak intensity increases.

5. The laser according to claim 1, wherein The laser is used in optical communication or multi-color display systems.

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