Tunable low power piezo-plasmonic random laser under external voltage

Journal Pre-proof Tunable Low Power Piezo-Plasmonic Random Laser under External Voltage S.F. Haddawi, H.R. Humud, S.M. Hamidi

PII:

S0030-4026(20)30316-8

DOI:

https://doi.org/10.1016/j.ijleo.2020.164482

Reference:

IJLEO 164482

To appear in:

Optik

Received Date:

6 November 2019

Revised Date:

27 February 2020

Accepted Date:

27 February 2020

Please cite this article as: Haddawi SF, Humud HR, Hamidi SM, Tunable Low Power Piezo-Plasmonic Random Laser under External Voltage, Optik (2020), doi: https://doi.org/10.1016/j.ijleo.2020.164482

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2020 Published by Elsevier.

Tunable Low Power Piezo-Plasmonic Random Laser under External Voltage S. F. Haddawi1,3, H. R. Humud3, S. M. Hamidi1* 1Magneto-plasmonic

lab, Laser and plasma Research Institute, Shahid Beheshti University, Tehran, Iran.

2Department

of Physics, College of Science, University of Baghdad, Baghdad, Iraq.

ro of

*Corresponding author: [email protected]

Abstract:

This study was aimed to introduce a new kind of low power and tunable random

-p

lasers based on piezo-plasmonic core/shell nanoparticles (NPs) consisting of lead

re

zirconate titanate and gold, mixed by different concentrations of Rhodamine B (RhB) dye. To get the random lasing, the sample was exposed to pulsed laser at the presence and in

lP

the absence of an external voltage. We got a gradual increase in the thermo-plasmonic properties by increasing the applied voltage on core/shell NPs, which depended on the

na

boundary conditions between the shell and the core samples. By external voltage, the emission intensity was enhanced by decreasing the threshold lasing due to an increase

ur

in scattering, which more easily made a close loop path in the gain medium. Our results showed some spikes with the same pump energy in emission spectrum which confirmed

Jo

the coherence random lasing. This phenomenon could be observed in PZT@Au NPs and it could not be observed in Au@PZT NPs in low and high concentrations. Furthermore, in lower pump energy, we observed low peak intensity in the emission spectrum and it increased as the pump energy overrode the lasing threshold. The emission spectrum became narrow with a sharp increase in the emission intensity, which we could reach a rapid decrease in the full width at half maximum (FWHM) of 1

the emission intensity above the threshold. These results showed the possibility of using these new kinds of materials for low threshold and controllable random lasing.

Keywords: random laser, piezo-plamsonic, thermo-plasmonic, Au@PZT, PZT@Au core/shell NPs, external voltage.

I.

Introduction

ro of

Random laser (RL) has many unique features, which was observed during the latest years in various kinds of disordered gain media due to light scattering instead of

reflection that is common in regular laser. In this case, light is confined by a disordered

-p

medium that scatters the light constantly on a microscopic length scale, and therefore

delays it from leaving the active area up to the limit of weak localization [1]. The

re

enhancement in effective cross-section of multiple light scattering can be achieved by implementation of localized surface plasmon resonance (LSPR) of nanoparticles

lP

generated in active medium, which results in significant property that is low lasing

na

threshold [2,3].

There are two main material choices for getting random lasing as a thin film or in a

ur

liquid medium. But the optical confinement, repeatability and stability in solid-state random lasers are sometimes better than that of dye random lasers [4,5]. For this reason, the scientists are

Jo

drifted to use semiconductor based nanoparticles (NPs) like metal/ semiconductor in the dye media. The noble metal/ semiconductor as a new kind of NPs named as piezo-plasmonic ones can act as a good gain candidate in low power random lasing because of the main role of Schottky barrier in the lasing control [6]. Nowadays there is a tunable random laser based on liquid crystals [7,8] which possesses the special features of tunability or flexible controllability in their lasing characteristics (e.g., energy 2

threshold or lasing wavelength) by thermal [9], electric [10,11], and optical [12] approaches. By adding the liquid crystals into the disordered nanostructures, the wavelength of random lasing can be tuned by heat or electricity, which in addition, enables us to bring the random laser above and below its threshold by temperature tuning of the diffusion constant. This phenomenon happens because the liquid crystal behaves as a normal isotropic liquid [13]. Thus, the refractive index can be tuned by changing the temperature and the electric field [14,15]. However, all of them are in the middle or high threshold power. There is an open question until now about the low power and

ro of

tunable lasing in these areas. We suppose that tunable low power piezo-plamsonic random laser have been achieved under external voltage as a first time. This is due to this fact that the electron

cloud of the piezoelectric NPs can be changed under the external voltage. In addition, we have

-p

studied the thermo-plasmonic properties for core/shell NPs under external electric field by throwing a voltage directly on both sides of the samples. On the other hand, Lead zirconate

re

titanate Pb(ZrxTi1-x)O3 (PZT) is one of the most studied pervoskite type ferroelectric

lP

materials due to its excellent dielectric, piezoelectric and ferroelectric properties in piezo-photonic area [16-18].

na

Based on above mentioned topics, we want to introduce a new kind of low power and tunable random lasers based on piezo-plasmonic NPs such as PZT@Au, Au@ PZT.

ur

These NPs were synthesized using laser ablation in liquid (LAL) method to reach the effect of interface of core-shell NPs as scattering points in the gain medium system. Experimental part:

Jo

II.

It is well known that the amplification in the dye gain medium and the lasing threshold in the random laser system depend on the size of NPs and the scattering cross section. Therefore, it is necessary to produce the optimal size of NPs inside the gain medium to increase light scattering. For this reason, we prepared four different kinds of NPs 3

including Au and PZT NPs, PZT@Au and Au@PZT core/shell NPs by laser ablation in liquids (LAL) method (Fig. 1) using first harmonic of Q-switched Nd:YAG laser with fixed energy at 100 mJ, repetition rate of 10 Hz and a pulse width of 5 ns. These parameters were suitable to produce the required size of NPs like our previous paper [19, 20]. The real image of these prepared samples as S1: Au NPs, S2: Au@PZT, S3: PZT@Au and S4: PZT NPs is shown in Fig. 1. Pure NPs were synthesized in distilled water and core-shell ones were formed in semi medium

ro of

with programmed time to get the better diameter of the core and the thickness of the shell. After examining them with field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM), they were mixed by different concentration of Rhodamine B

Jo

ur

na

lP

re

-p

(RhB) dye.

Fig. 1: Schematic of the experimental setup used for nanoparticles preparation by laser ablation in a liquid medium and the real picture of the prepared samples.

Afterwards, we examined the above -mentioned NPs under green pulsed laser under low, 0.13mJ, and high 1.95mJ, power as shown in Fig. 2. In this experimental setup, the sample was exposed 4

to pulsed laser with and without external voltage and the scattered light were collected by

ro of

computer-connected spectrometer in 40 degree.

Fig. 2: Schematic of the experimental setup used for random laser under green light pumping.

-p

Finally, the thermo-plasmonic picture of the sample was recorded under the green light pump, and external voltage by a thermal imaging camera (type of FLIR) for

re

determining thermo-plasmonic properties of the samples, as shown schematically in

Jo

ur

na

lP

Fig. 3.

Fig. 3: Schematic diagram of thermo-plasmonic measurement setup.

We used (532 nm) Nd:YAG pulsed laser with a fixed energy at 30 mJ, repetition rate of 10 Hz and a pulse width of 5 ns during 30 seconds for sample illumination. External voltage of 0-15 volt directly affected the prepared samples in this work. 5

III.

Results and Discussion:

Fig (4a) shows the transmission electron microscopy (TEM) image of PZT@Au NPs which were dropped onto the glass substrate, the size ranges from 30 to 50 nm for core and 3 to 8 nm for shell in deionized water solution. Fig (4 b,c) shows FE-SEM (Field Emission Scanning Electron Microscopes) image of PZT@Au NPs where the

ro of

size ranges from 20 to 60 nm for core and 3 to 8 nm for the shell and Au@PZT NPs with core-size between 20 to 40 nm and shell-size between 2 to 6 nm in deionized water

lP

re

-p

solution, respectively.

(a)

(b)

(c)

na

Fig.4(a) TEM image of TEM PZT@Au NPs, (b) FE-SEM image of PZT@Au NPs, and (c) FE-SEM image of Au@PZT NPs.

ur

The absorption spectra of prepared nanoparticles in distilled water confirm the position of absorption due to SPR or another mechanism, shown in Fig. 5a. In addition, the

Jo

absorption spectra of NPs and core-shell mixed with RhB at the same concentrations (1.5×10-5 Mol/L) are shown in Fig. 5b, 5c,5d.

6

1.4 1.2

Absorbance (a.u.)

Absorbance (a. u.)

(a) 0.12

0.08

1.0 0.8 0.6 0.4

0.04

0.2 0.0

0.00 300

400

500

600

700

0.1 mLAu@PZT + 0.9 mL RhB (1.5*10-5 mol/L) 0.5 mLAu@PZT + 0.5 mL RhB (1.5*10-5 mol/L)

1.6

Au@PZT PZT@Au

0.16

(a) 400

800

500

(nm)

600

700

800

(nm)

0.6 0.4 0.2

0.8 0.6 0.4 0.2

( c)

0.0

(d)

0.0 400

400

500

600

700

ro of

0.8

1.0

0.1 mL PZT + 0.9 mL RhB(1.5*10-5 Mol/L) 0.5 mL PZT + 0.5 mL RhB(1.5*10-5 Mol/L)

1.0

1.2 Absorbance (a.u.)

Absorbance (a.u.)

1.2

1.4

0.5 mL PZT@Au + 0.5 mL RhB (1.5*10

1.4

0.1 mL PZT@Au + 0.9 mL RhB (1.5*10-5 Mol/L) -5 Mol/L)

1.6

800

600 (nm)

700

800

-p

(nm)

500

re

Fig.5: Absorption spectra of the (a) PZT@Au and Au@PZT NPs, and (b,c,d) different concentrations of PZT, PZT@Au and Au@PZT NPs mixed with RhB at the same concentration (1.5*10-5 Mol/L).

lP

Furthermore, one can see a red shift at two different concentrations of NPs into dyes, from low concentrations of NPs, 10%, to high concentrations, 50% in the wavelength

na

range from 545 nm to 550 nm.

We are realizing that piezo-plasmonic nanoparticles can play a role as effective sources

ur

of heat generation. Therefore, the Au@PZT NPs, and PZT@Au NPs can be considered as heat sources when they are irradiated by lasers or affected by direct external fields

Jo

on the samples. When an external electric field was applied to Au/PZT core/shell NPs, the polarization reversal phenomenon occurred which led to an increase in linear and nonlinear refractive indices of Au/PZT core/shell NPs. In addition, this external field may lead to thermal effects like increasing the local temperature via thermo-plasmonic properties of the samples [21-26].

7

The PZT NPs have special piezoelectric properties, which are enhanced when synthesized in the form of metal/ semiconductor core/shell nanostructures. Now we are studying thermo-plasmonic properties of Au/PZT core/shell NPs under external voltage. Using the thermal camera, we can record the thermal images for the Au/PZT NPs samples under applying a variable external voltage (0–15volt), in order to study the effect of the external electric field on the thermo-plasmonic properties of these NPs. Our results have shown that an increase in the applied voltages leads to temperature

ro of

elevation of samples as shown in Fig. 6.

PZT@Au

PZT@Au

PZT@Au

PZT@Au

re

36

Au@PZT PZT@Au

lP

34

32

Temperature (c)

-p

10V

na

30

28

ur

26

24

Jo

-5

0V

Au@PZT

0

5

10

15

20

Applied voltages (volt)

10V

5V

Au@PZT

Au@PZT

Fig.6: Experimental heat generation of PZT@Au NPs, and Au@PZT NPs in deionized water under external voltage.

8

15V

Au@PZT

We obtained a gradual increase in the thermo-plasmonic properties due to voltage effect about ∆𝑇 = 10.3𝐶 𝑜 for Au@PZT NPs, and ∆𝑇 = 9.8𝐶 𝑜 for PZT@Au NPs. This change is increased by increasing the applied voltage on core/shell NPs, which depends on the boundary conditions between the shell and the core and the height of the Schottky barrier in core/shell samples.

ro of

The thermal images gave a clear behavior about the mechanism of converting light to heat in the nanoparticle samples. This conversion depended on the density of nanoparticle distribution, and the type of nanomaterial in the sample since the thermal

-p

response to the samples increased by increasing the number of nanoparticles in the cell. When light was absorbed by nanoparticles, the energy from the excited electronic states

re

was transferred to the phonons (the mechanism of photon-energy (hν) absorption) which intensified the lattice vibrations. This absorption depended on the electronic

lP

structure of a material. The laser-instigated interband or intraband electronic transition induced a non-equilibrium electronic distribution that heated the materials by

na

electron/phonon and electron/electron interactions. The heating led to the reestablishment of the equilibrium condition by the electron/hole recombination process

ur

during a specified time depending on the material characteristics. The general effect is

Jo

the transformation of electronic energy obtained from the incident laser into heat. This strategy was essentially found on the photo-thermal effect incited by a focused laser. The laser remotely created a limited temperature field at an ideal position with high controllability in the wavelength, energy and pulse width of the laser. The absorption phenomenon was usually associated with the scattering of laser radiation, leading to attenuation and spatial redistribution (diffusion) of the laser beam energy [21-26].

9

For better understanding the physical effect of thermo-plasmonic on random lasing, we clarified the samples under pulsed laser excitation. For this reason, we recorded the heating process under the main pump pulsed laser which we used in random lasing. As seen in Fig. 7, PZT@Au NPs had a higher temperature than the Au@PZT core shell NPs because the gold layer represented a shell here that increased light harvesting. Therefore, the SPR peak was close to the excitation wavelength (532 nm). Au@PZT NPs

-p

ro of

PZT@Au NPs

re

Fig.7: Experimental heat generation by 532nm, 30mJ laser pulse illumination of (a) Au@PZT NPs in deionized water and (b) PZT@Au NPs in deionized water.

The experimental results show that the illumination of the Au/PZT core/shell NPs

lP

samples by the laser led to temperature elevation at a rate of change ∆𝑇 = 14.1𝐶 𝑜 , and 13.4 𝐶 𝑜 for PZT@Au, and Au@PZT NPs as compared with the sample at room

na

temperature and without any pump or external voltage (as shown in Fig. 6) respectively. The boundary conditions between core and shell led to the redistribution of an

ur

electron/hole pair in the metal/semiconductor interfaces that resulted in different height of the Schottky barrier between samples. According to this fact, we plotted the Schottky

Jo

barrier of this sample as shown in Fig. 8.

10

ro of

Fig.8: Schottky junction showing the band bending on the PZT NPs side. PZT bands bend up going from the PZT (positive) to Au (negative) since this is the same direction as the electric field.

The combination of Au NPs as cores into the PZT NPs as shells reasonably decreased

-p

the band gap and thus the electron-hole pair recombination rate became slower while

re

resulting in a faster electron transfer, which maybe can be assigned as the main physical reason to this higher temperature and our expected higher random lasing efficiency

lP

[27]. Then we studied the random lasing in the above-mentioned classes with different concentrations and different core-shell NPs with the same dye concentration.

na

A. Random laser by PZT@Au and Au@PZT NPs

ur

We have inserted the noble metal/semiconductor NPs as a new kind of NPs into

Jo

our main gain media. These NPs, as piezo-plasmonic ones, maybe have well gain in low power random lasing (PZT@Au) and (Au@PZT) because of the fact that explained before.

11

21900

PZT@Au

17100 21300

Au@PZT

Intensity (a. u.)

21600

21000 10%, 1.95 mJ

550

560

570

Intensity (a. u.)

17400

16800

580

590

600

(nm)

ro of

560

570

580

590

3900 600

-p

(nm)

1800

3500

1700

3400

1600

PZT@Au

3200 550

50%, 0.13 mJ

560

570

580 (nm)

Intensity (a. u.)

11400

13500

50%, 1.95 mJ

560

570

580

590

600

Intensity (a. u.)

ur

3600

Au@PZT

11700

(nm)

1900

3300

PZT@Au

13800

13200 550

3700

Jo

Intensity (a. u.)

na

lP

re

(a)

1500

590

600

1400 610

(b) Fig. 9: Emission spectra of (a) low (0.1 ml NPs+ 0.9 ml RhB 1.5*10-5 mol/L) and (b) high concentration (0.5 ml NPs+ 0.5 ml RhB 1.5*10-5 mol/L) of Au@PZT and PZT@Au NPs from low to high pump intensities and the comparison between the lowest (0.13mJ) and highest (1.95 mJ) pump energies.;

12

11100 610

Intensity (a. u.)

10%, 0.13 mJ

Au@PZT

4800

550

Intensity (a. u.)

4200

Au@PZT

Intensity (a. u.)

4500 PZT@Au

5100

We studied the threshold lasing and emission intensity of two different concentrations, 10% and 50%, with different pump energy below, (0.13 mJ), and above leasing threshold,)1.95 mJ(, for each of the PZT@Au and Au@PZT NPs as shown in Fig. 9. In the low concentrations of PZT@Au NPs, 10%, at lower pump energy (0.13 mJ), we observed the lasing threshold higher than that higher concentrations, 50%, with the same pump energy because of its much smaller scattering cross section. Based on this fact that the higher pump

ro of

threshold occurred far the edge of the diffusive regime corresponding to a scattering mean free path; in the first case with low concentration mixed with RhB, enhancement in the scattering mean free path could produce greater lasing threshold. In addition, the lasing peak

-p

was observed with low (high) concentration at 580 nm (575 nm) with number of less than 0.5 nm spikes respectively.

re

On the contrary, at lower pump energy, we observed low peak intensity in the emission

lP

spectrum and it increased as the pump energy overrode the lasing threshold. The emission spectrum became narrow with a sharp increase in the emission intensity, which could achieve a rapid decrease in (FWHM) of the emission intensity above the threshold, and the number

na

of spikes for each concentration was less than 0.3 nm. For PZT@Au, we could observe the emission intensity higher than that in Au@PZT. In

ur

addition, the lasing threshold was lower in this case as shown in Fig. 10. The reason is that

Jo

plasmonic metals/semiconductors permitted the integrated featured functions of two nano systems into one nano system to get the coupling to enhance the emission intensity with lower pump energy.

13

5400

4500

PZT@Au at 0.13 mJ

2000

0.1 ml of NPs 0.5 ml of NPs

5200

Au@PZT at 0.13 mJ

3600

4400

0.1 ml of NPs 0.5 ml of NPs

1900

4300

5000

4200 3400

4100

1600

4400

Intensity (a. u.)

1700

4600

Intensity (a. u.)

4800

Intensity (a. u.)

Intensity (a. u.)

3500 1800

4000 3300 3900

1500

4200

4000

3200

1400 540

550

560

570

580

590

600

610

3800 540

620

550

560

570

580

590

600

610

620

(nm)

(nm) 11900 PZT@Au at 1.95 mJ

21800

Au@PZT at 1.95 mJ

17400

11800

0.1 mL of NPs

0.1 ml of NPs

11400

21200

13800

13700

17000

13600

13500

11300 16800

21000 11200 20800

13400

11100 540

550

560

570

580

590

600

610

Intensity (a. u.)

11500

17200

ro of

21400

Intensity (a. u.)

11600

Intensity (a. u.)

11700

21600

Intensity (a. u.)

13900

0.5 ml of NPs

0.5 mL of NPs

14000

16600

620

13300

540

(nm)

550

560

570

580

590

600

610

620

-p

(nm)

lP

re

Fig 10(a) Emission intensity of PZT@Au and Au@PZT NPs with different concentrations (0.1 and 0.5 mL) at low pump energy (0.13 mJ), emission intensity of PZT@Au and Au@PZT NPs with different concentrations (0.1 and 0.5 mL) at high pump energy (1.95 mJ).

The plasmon-induced hot electron injection from Au to PZT in Au/PZT NPs, could be

na

an interesting phenomenon to enhance the random lasing intensity. Furthermore, the local electromagnetic field enhancement due to thermo-plasmonic phenomena acted as

ur

an efficient tool to change the above-mentioned threshold. Thus we want to exam the effect of this thermo-plasmonic effect onto the random lasing threshold and efficiency under

Jo

external voltage.

14

B. PZT, PZT@Au and Au@PZT NPs at different voltages with lower pump energy

We have studied electrically the controllable random lasers in different styles of piezoelectric-based NPs mixed with dye under external electric field. At first step, to get the random laser by low and high concentrations of PZT NPs, we investigated the effect of PZT NPs on the laser properties of the RhB laser dye in the methanol solvent. As shown in Fig. 11, the lasing intensities increased with the same pump energy (0.17mJ) by increasing

15

0.5 mL PZT + 0.5 mL RhB at 0.17mJ

5600

10

5

6900

5200

10

4800

-p

7200

0V 5V 10V 15V

15

7500

Intensity (a.u)

Intensity (a.u)

7800

6000

0V 5V 10V 15V

0.1 mL PZT + 0.9 mL RhB at 0.17mJ

8100

ro of

the applied voltage in the gain medium.

4400

6600

0

5

6300

4000

550

560

570

580

(nm)

590

600

610

620

540

550

0

560

570

580 590 (nm)

(b) 600

610

620

630

640

lP

540

re

(a)

na

Fig. 11: Emission intensity of PZT NPs in different concentrations under 0, 5, 10 and 15 V.

This increase in the lasing under external electric field was due to the effective increase in

ur

the spatial fluctuation of the orientation order and thus in the dielectric property of the gain medium. For this reason, scattering mean free path of the fluorescence photons in their

Jo

recurrent multi-scattering enhanced, leading to an increase in the lasing intensity of the random lasers and the decrease in their energy thresholds. In other words, by external voltage, the emission intensity enhanced with lower threshold lasing due to an increased scattering with this voltage, which made a close loop path and some spikes with the same pump energy. This phenomenon could be observed in PZT@Au NPs and it could not be observed in Au@PZT NPs in low and high concentrations. This fact can be arisen from the 15

multi-domain nature in PZT piezoelectric material into the PZT@Au NPs as compared to its single domain nature in the Au@PZT structure. This single domain nature could be influenced a little by external voltage, which was confirmed by our results in the emission intensity and the number of spikes (Fig. 12). 1700

0.1 ml Au@PZT + 0.9 ml RhB 1.5x10-5 mol/L at 0.17 mJ

0.5 ml Au@PZT + 0.5 ml RhB (1.5x10-5 mol/L) at 0.17 mJ

2300 0V 5V 10V 15V

1600

2200

Intensity (a.u)

2000 1900

1300

1200

1800 1700

1400

0V 5V 10V 15V

(a)

550

560

570

580

590

600

1100

610

(b)

550

(nm) 2600

5500

ro of

Intensity (a.u)

1500

2100

560

570

580 (nm)

590

600

610

0.5 ml PZT@Au + 0.5 ml RhB 1.5x10-5 mol/L at 0.17 mJ

0.1 ml PZT@Au + 0.9 ml RhB (1.5x10-5 mol/L) at 0.17 mJ 2400

15

5000

-p

2200

Intensity (a.u.)

10

4000

3500

5

3000

(c) 560

580

lP

0

540

10

1800

1600

5

1400

0V 5V 10V 15V

2500

2000

2000

re

Intensity (a. u.)

15 4500

600

640

0V 5V 10 V 15 V

1000

540

560

580

 (nm)

600

620

na

(nm)

620

0

1200

ur

Fig. 12: Emission intensity of (a) 0.1 ml and (b) 0.5 ml concentrations of Au@PZT and PZT@Au NPs under different voltage and low pump power set to 0.17 mJ.

Jo

In addition, the same behavior about obtaining a better gain in Au@PZT in comparison with the PZT@Au in the same pump energy was repeated due to the SPR of the gold core in these samples under external voltages (Fig. 13).

16

640

2100 4800

10% and 10 V

PZT@Au Au@PZT

4600

2000

4200

1900

4000 3800

1800

Au@PZT NPs

PZT@Au NPs

4400

3400

1700

Au@PZT

3200

(a)

3000

1600

560

570

580

2000

1600

1500

1400

1300

ur

1400

620

na

1800

610

PZT@Au Au@PZT

lP

0.5 ml and 10 V

1600

600

re

 (nm)

590

Au@PZT NPs

550

-p

540

PZT@Au NPs

ro of

3600

1200

Jo

1200

1100

(b)

1000

1000 540

550

560

570

580

590

600

610

620

 (nm)

Fig. 13: Comparison of the emission intensity of (a) 0.1 ml and (b) 0.5 ml concentrations of PZT@Au and Au@PZT NPs under fixed voltage set to 10 V.

17

IV.

Conclusion: The piezo-plasmonic random lasing was demonstrated with PZT@Au and Au@PZT NPs

to get better response by lower threshold power. It was observed that the scattering mean

free path with lower voltage was smaller than the length of the scattering in the gain medium. Due to the existence of piezoelectric NPs in the gain medium and their dependency on the external voltage, the emission intensity enhanced with lower

ro of

threshold power due to an increase in the scattering mean free path. This fact is confirmed in the Au@PZT sample due to the polarization domain in the PZT shell. In addition, we had another important parameter to change pump power threshold under

-p

external voltage which came from the thermoplasmonic characteristic under laser

re

excitation.

lP

Declaration of interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

na

Reference:

[1] Fallert, J., R.J.B. Dietz, M. Hauser, F. Stelzl, C. Klingshirn, and H. Kalt. "Random lasing in ZnO nanocrystals." Journal of Luminescence 129, no. 12 (2009), 1685-1688. doi:10.1016/j.jlumin.2009.02.022.

ur

[2] Zhai, Tianrui, Zhiyang Xu, Songtao Li, and Xinping Zhang. "Red-green-blue plasmonic random laser." Optics Express 25, no. 3 (2017), 2100. doi:10.1364/oe.25.002100.

Jo

[3] Tong, Junhua, Songtao Li, Chao Chen, Yulan Fu, Fengzhao Cao, Lianze Niu, Tianrui Zhai, and Xinping Zhang. "Flexible Random Laser Using Silver Nanoflowers." Polymers 11, no. 4 (2019), 619. doi:10.3390/polym11040619. [4] Lee, Ya-Ju, Chun-Yang Chou, Zu-Po Yang, Thi B. Nguyen, Yung-Chi Yao, TingWei Yeh, Meng-Tsan Tsai, and Hao-Chun Kuo. "Flexible random lasers with tunable lasing emissions." Nanoscale 10, no. 22 (2018), 10403-10411. doi:10.1039/c8nr00229k. [5] Zhai, Tianrui, Jie Chen, Li Chen, Jieyu Wang, Li Wang, Dahe Liu, Songtao Li, Hongmei Liu, and Xinping Zhang. "A plasmonic random laser tunable through stretching silver nanowires embedded in a flexible substrate." Nanoscale 7, no. 6 18

(2015), 2235-2240. doi:10.1039/c4nr06632d. [6] Long, Li, Daisi He, Weiying Bao, Menglei Feng, Peng Zhang, Dingke Zhang, and Shijian Chen. "Localized surface plasmon resonance improved lasing performance of Ag nanoparticles/organic dye random laser." Journal of Alloys and Compounds 693 (2017), 876-881. doi:10.1016/j.jallcom.2016.09.246. [7] Wan, Yuan, Yashuai An, and Luogen Deng. "Plasmonic enhanced low-threshold random lasing from dye-doped nematic liquid crystals with TiN nanoparticles in capillary tubes." Scientific Reports 7, no. 1 (2017). doi:10.1038/s41598-017-16359-5.

ro of

[8] Shasti, M., P. Coutino, S. Mukherjee, A. Varanytsia, T. Smith, A. P. Luchette, L. Sukhomlinova, T. Kosa, A. Munoz, and B. Taheri. "Reverse mode switching of the random laser emission in dye doped liquid crystals under homogeneous and inhomogeneous electric fields." Photonics Research 4, no. 1 (2016), 7. doi:10.1364/prj.4.000007. [9] Lee, Chia-Rong, Shih-Hung Lin, Jin-Wei Guo, Jia-De Lin, Hong-Lin Lin, YangChen Zheng, Chia-Lien Ma, Chi-Ting Horng, Han-Ying Sun, and Shuan-Yu Huang. "Electrically and thermally controllable nanoparticle random laser in a well-aligned dye-doped liquid crystal cell." Optical Materials Express 5, no. 6 (2015), 1469. doi:10.1364/ome.5.001469.

-p

[10] Song, Qinghai, Liying Liu, Lei Xu, Yonggang Wu, and Zhanshan Wang. "Electrical tunable random laser emission from a liquid-crystal infiltrated disordered planar microcavity." Optics Letters 34, no. 3 (2009), 298. doi:10.1364/ol.34.000298.

lP

re

[11] Chen, Peiliang, Xiangyang Ma, Dongsheng Li, Yuanyuan Zhang, and Deren Yang. "Electric-field-induced random lasing from ZnO and Mg_01Zn_09O films optically pumped with an extremely low intensity." Optics Express 17, no. 21 (2009), 18513. doi:10.1364/oe.17.018513.

na

[12] Ferjani, Sameh, Valentin Barna, Antonio De Luca, Carlo Versace, and Giuseppe Strangi. "Random lasing in freely suspended dye-doped nematic liquid crystals." Optics Letters33, no. 6 (2008), 557. doi:10.1364/ol.33.000557.

ur

[13] Chen, Ziping, Dechun Hu, Xingwu Chen, Deren Zeng, Yungjui Lee, Xiaoxian Chen, and Jiangang Lu. "Templated Sphere Phase Liquid Crystals for Tunable Random Lasing." Nanomaterials 7, no. 11 (2017), 392. doi:10.3390/nano7110392.

Jo

[14] Mujumdar, Sushil, Stefano Cavalieri, and Diederik S. Wiersma. "Temperaturetunable random lasing: numerical calculations and experiments." Journal of the Optical Society of America B 21, no. 1 (2004), 201. doi:10.1364/josab.21.000201. [15] Mbarak, H., A.K. Kodeary, S.M. Hamidi, E. Mohajarani, and Y. Zaatar. "Control of nonlinear refractive index of AuNPs doped with nematic liquid crystal under external electric field." Optik 198 (2019), 163299. doi:10.1016/j.ijleo.2019.163299.

[16] Eiras, José, Rosimeire Gerbasi, Jaciele Rosso, Daniel Silva, Luiz Cótica, Ivair Santos, Camila Souza, and Manuel Lente. "Compositional Design of Dielectric, Ferroelectric and Piezoelectric Properties of (K, Na)NbO3 and (Ba, Na)(Ti, Nb)O3 Based Ceramics Prepared by Different Sintering Routes." Materials 9, no. 3 (2016), 179. doi:10.3390/ma9030179. [17]

Izyumskaya, N., Y.-I. Alivov, S.-J. Cho, H. Morkoç, H. Lee, and Y.-S. Kang. 19

"Processing, Structure, Properties, and Applications of PZT Thin Films." Critical Reviews in Solid State and Materials Sciences 32, no. 3-4 (2007), 111-202. doi:10.1080/10408430701707347. [18] Arul, K. T., M. Ramanjaneyulu, and M.S. Ramachandra Rao. "Energy harvesting of PZT/PMMA composite flexible films." Current Applied Physics 19, no. 4 (2019), 375-380. doi:10.1016/j.cap.2019.01.003. [19] Kodeary, A. K., and S. M. Hamidi. "Tunable Piezophotonic Effect on Core-Shell Nanoparticles Prepared by Laser Ablation in Liquids under External Voltage." Journal of Nanotechnology 2019 (2019), 1-11. doi:10.1155/2019/6046079. [20] S. F. Haddawi, Hammed R. Humud, S. M. Hamidi, "Signature of plasmonic nanoparticles in multiwavelength low power random lasing", Under revision in Optics and Laser Technology (2019).

ro of

[21] M. Gatea, Et al. "Thermoplasmonic of Single Au@SiO2 and SiO2@Au Core Shell Nanoparticles in Deionized Water and Poly-vinylpyrrolidoneMatrix." Baghdad Science Journal 16, no. 2 (2019), 0376. doi:10.21123/bsj.16.2.0376.

-p

[22] S. F. Haddawi, J. A. Abd, W. Mnati, H. A. majeed, "Study of the Properties of laser Beam Propagation through the Reactive Red dye." International Journal of ChemTech Research (2016), 9 No.12, pp 767-773.

re

[23] Palneedi, Haribabu, Jung H. Park, Deepam Maurya, Mahesh Peddigari, Geon-Tae Hwang, Venkateswarlu Annapureddy, Jong-Woo Kim, et al. "Laser Processing of Metal Oxides: Laser Irradiation of Metal Oxide Films and Nanostructures: Applications and Advances (Adv. Mater. 14/2018)." Advanced Materials 30, no. 14 (2018), 1870094. doi:10.1002/adma.201870094.

lP

[24] Howard, Tyler V., Jeremy R. Dunklin, Gregory T. Forcherio, and D. K. Roper. "Thermoplasmonic dissipation in gold nanoparticle–polyvinylpyrrolidone thin films." RSC Advances 7, no. 89 (2017), 56463-56470. doi:10.1039/c7ra03892e.

ur

na

[25] Gatea, Maher A., Hussein A. Jawad, and S. M. Hamidi. "Detecting the thermoplasmonic effect using ellipsometry parameters for self-assembled gold nanoparticles within a polydimethylsiloxane matrix." Applied Physics A 125, no. 2 (2019). doi:10.1007/s00339-019-2401-7.

Jo

[26] Abadeer, Nardine S., and Catherine J. Murphy. "Recent Progress in Cancer Thermal Therapy Using Gold Nanoparticles." The Journal of Physical Chemistry C 120, no. 9 (2016), 4691-4716. doi:10.1021/acs.jpcc.5b11232. [27] Tan, Zhengwei, Lanqing Hong, Zhen Fan, Junjiang Tian, Luyong Zhang, Yue Jiang, Zhipeng Hou, et al. "Thinning ferroelectric films for high-efficiency photovoltaics based on the Schottky barrier effect." NPG Asia Materials 11, no. 1 (2019). doi:10.1038/s41427-019-0120-3.

20